Refactor file writing - information on our use of Perl and Perl modules

This includes a start on how to install missing modules.
Reviewed-by: NRich Salz <rsalz@openssl.org>

INSTALL

@@ -12,7 +12,8 @@
  To install OpenSSL, you will need:
 
   * make
-  * Perl 5 with core modules (see 'Note on Perl' further down)
+  * Perl 5 with core modules (please read README.PERL)
+  * The perl module Text::Template (please read README.PERL)
   * an ANSI C compiler
   * a development environment in form of development libraries and C
     header files
@@ -310,26 +311,6 @@
      with names of the form <foo.h>.
 
 
- Note on Perl
- ------------
-
- For our scripts, we rely quite a bit on Perl, and increasingly on
- some core Perl modules.  These Perl modules are part of the Perl
- source, so if you build Perl on your own, you should be set.
-
- However, if you install Perl as binary packages, the outcome might
- differ, and you may have to check that you do get the core modules
- installed properly.  We do not claim to know them all, but experience
- has told us the following:
-
- - on Linux distributions based on Debian, the package 'perl' will
-   install the core Perl modules as well, so you will be fine.
- - on Linux distributions based on RPMs, you will need to install
-   'perl-core' rather than just 'perl'.
-
- It is highly recommended that you have at least Perl version 5.12
- installed.
-
  Note on multi-threading
  -----------------------
 

INSTALL.DJGPP

@@ -11,7 +11,8 @@
 
  You should have a full DJGPP environment installed, including the
  latest versions of DJGPP, GCC, BINUTILS, BASH, etc. This package
- requires that PERL and BC also be installed.
+ requires that PERL and the PERL module Text::Template also be
+ installed.
 
  All of these can be obtained from the usual DJGPP mirror sites or
  directly at "http://www.delorie.com/pub/djgpp". For help on which

INSTALL.WCE

@@ -8,6 +8,8 @@
   * Appropriate SDK might be required
   * Perl for Win32 [commonly recommended ActiveState Perl is available
     from http://www.activestate.com/Products/ActivePerl/]
+    You also need the perl module Text::Template.
+    Please read README.PERL for more information.
 
   * wcecompat compatibility library available at
     http://www.essemer.com.au/windowsce/

INSTALL.WIN

@@ -6,8 +6,10 @@
 
  Here are a few comments about building OpenSSL for Windows environments.
 
- - you need Perl.  Unless you will build on Cygwin, you will
-   need ActiveState Perl, available from http://www.activestate.com/ActivePerl.
+ - you need Perl.  Unless you will build on Cygwin, you will need
+   ActiveState Perl, available from http://www.activestate.com/ActivePerl.  
+   You also need the perl module Text::Template, available on CPAN.
+   Please read README.PERL for more information.
 
  - one of the following C compilers:
 

README.PERL

+ TOC
+ ===
+
+ - Notes on Perl
+ - Notes on Perl on Windows
+ - Notes on Perl modules we use
+ - Notes on installing a perl module
+
+ Notes on Perl
+ -------------
+
+ For our scripts, we rely quite a bit on Perl, and increasingly on
+ some core Perl modules.  These Perl modules are part of the Perl
+ source, so if you build Perl on your own, you should be set.
+
+ However, if you install Perl as binary packages, the outcome might
+ differ, and you may have to check that you do get the core modules
+ installed properly.  We do not claim to know them all, but experience
+ has told us the following:
+
+ - on Linux distributions based on Debian, the package 'perl' will
+   install the core Perl modules as well, so you will be fine.
+ - on Linux distributions based on RPMs, you will need to install
+   'perl-core' rather than just 'perl'.
+
+ It is highly recommended that you have at least Perl version 5.10
+ installed.
+
+ Notes on Perl on Windows
+ ------------------------
+
+ If you will build on Cygwin (and possibly some other POSIX layers),
+ Perl is already part of your distribution.  Simply use the Cygwin
+ package manager to make sure Perl gets installed.
+
+ Otherwise, you will need to install Perl separately.  The Perl
+ package that we know of is ActiveState Perl, available from
+ http://www.activestate.com/ActivePerl.
+
+ Notes on Perl modules we use
+ ----------------------------
+
+ We make increasing use of Perl modules, and do our best to limit
+ ourselves to core Perl modules to keep the requirements down.  There
+ are just a few exceptions:
+
+ Test::More         We require the minimum version to be 0.96, which
+                    appeared in Perl 5.13.4, because that version was
+                    the first to have all the features we're using.
+                    This module is required for testing only!  If you
+                    don't plan on running the tests, you don't need to
+                    bother with this one.
+
+ Text::Template     This module is not part of the core Perl modules.
+                    As a matter of fact, the core Perl modules do not
+                    include any templating module to date.
+                    This module is absolutely needed, configuration
+                    depends on it.
+
+ To avoid unnecessary initial hurdles, we have bundled a copy of the
+ following modules in our source.  They will work as fallbacks if
+ these modules aren't already installed on the system.
+
+    Text::Template
+
+ Notes on installing a perl module
+ ---------------------------------
+
+ There are a number of ways to install a perl module.  In all
+ descriptions below, Text::Template will server as an example.
+
+ 1. for Linux users, the easiest is to install with the use of your
+    favorite package manager.  Usually, all you need to do is search
+    for the module name and to install the package that comes up.
+
+    On Debian based Linux distributions, it would go like this:
+
+        $ apt-cache search Text::Template
+        ...
+        libtext-template-perl - perl module to process text templates
+        $ sudo apt-get install libtext-template-perl
+
+    Perl modules in Debian based distributions use package names like
+    the name of the module in question, with "lib" prepended and
+    "-perl" appended.
+
+ 2. Install using CPAN.  This is very easy, but usually requires root
+    access:
+
+        $ cpan -i Text::Template
+
+    Note that this runs all the tests that the module to be install
+    comes with.  This is usually a smooth operation, but there are
+    platforms where a failure is indicate even though the actual tests
+    were successful.  Should that happen, you can force an
+    installation regardless (that should be safe since you've already
+    seen the tests succeed!):
+
+        $ cpan -f -i Text::Template