This condition was added for cygwin support but appears to simply turn
off the normalization of CPU types

The version recognition was failing for version 1.11, thinking the
minor version was 1 rather than 11.

changed /configure to be compatible with Cygwin and removed annoying --help not a command available message

For cross compiling to targets that don't want to build a compiler

- thanks to work in libuv's upstream, we can call libuv's Makefile directly
with parameters, instead of descending in gyp-uv madness and generating
our own.

Ubuntu's clang packages have additional information appended to the end of
the version.

- Building Rust v0.5 with clang v3.0-6ubuntu3 fails.
- Building Rust v0.5 and incoming with clang v3.1-5ppa (backported from Debian)
works.

Closes #4441.

Conflicts:
	src/libcore/os.rs
	src/librustc/back/link.rs
	src/librustc/driver/driver.rs
	src/librustc/metadata/loader.rs
	src/librustc/middle/trans/base.rs

Add Brian Leibig to AUTHORS.txt for REPL contributions

These systems run 32 bit binaries so arch needs to be forced
to 32 bits.

Add GRSecurity compatibility with --enable-pax-marks configure flag; add GRSecurity autodetection code to configure.