Make `rails runner` command options more obvious

fix default select when from is used

We're surrounding the options in angle brackets `<>` as is convention in `curl`:

```
$ curl --help
Usage: curl [options...] <url>
```

And then in square brackets `[]` with bars `|` as in `tar`:

```
$ tar --help
...
Create: tar -c [options] [<file> | <dir> | @<archive> | -C <dir> ]
```

To further clarify that the command can be used with both, we now show examples:

```
Examples:
    rails runner 'puts Rails.env'
        This runs the code `puts Rails.env` after loading the app

    rails runner path/to/filename.rb
        This runs the Ruby file located at `path/to/filename.rb` after loading the app
```

This format was taken from the `find` man pages:

```
EXAMPLES
     The following examples are shown as given to the shell:

     find / \! -name "*.c" -print
             Print out a list of all the files whose names do not end in .c.

     find / -newer ttt -user wnj -print
             Print out a list of all the files owned by user ``wnj'' that are newer than the file ttt.
```

The the text at the bottom is also shifted to improve readability.

[ci skip]

This reverts commit 293a1a68.

Example code does not run yet with beta1.

Remove <tt> tag in 4_1_release notes. [ci skip].

This reverts commit 41ba51f4.

[ci skip]

This reverts commit f4804faf.

[ci skip]

This reverts commit 427db6b9.

[ci skip]

This reverts commit b58f3a64.

Reason: Discussion in https://github.com/rails/docrails/commit/b58f3a641795e1777aa3e12a853c34ff512acfb9

[ci skip]

Fixed configurable.rb regular expression name check

[ci skip] Remove <tt> tag in 4_1_release notes.

Prevent creation of instance methods when `instance_reader = false`, Grammar checks, Conditional statements combined

Prevent creation of instance methods when `instance_reader = false`, Grammar checks, Conditional statements combined

modified regex for finding table_name from a multiline sql query in postgresql

Previously, executing an insert SQL in PostgreSQL with a command like this:

    insert into articles(
      number)
    values(
      5152
    )

would not work because the adapter was unable to extract the correct articles table name.

Closes #9625

Change most tests to make use of assert_raise returning the raised
exception rather than relying on a combination of flunk + rescue to
check for exception types/messages.

In Minitest, the second argument of assert_raise(s) accepts a string as
the message that should be shown in case of a failure in the assertion
(eg nothing was raised when it should), and not the exception message to
be matched.

To do that we need to save the exception returned from assert_raise(s)
into a local variable and check for the exception message using it.

Add information about 'available_locales' and 'enforce_available_locales'
to the configuring guide.

Closes #13202. [ci skip]

Fix PostgreSQL range tests on fresh DB

Correcting the name of the table we're creating is self-explanatory.

But we must also move away from the low IDs, because we're not touching the freshly-created primary key sequence; when the time comes, @new_range will be assigned an ID of 1.

fix typos and grammar mistake [ci skip]

set encoding UTF-8 for accepting multibyte character