Ignore the 'brew leaves' command. Refs #357
Added externals directory to XHGUI install

The externals directory contains header and footer files which can be included to run XHGUI on your scripts.
OAuth 1.2.3
Friendly response on Composer requirement failure
Updated sha on php-cs-fixer
Updated super call in abstract-php-extension
Add header files for igbinary
Added igbinary support to memcached. Closes #376
Add support for igbinary to redis extension
No longer build with inline intl support

As of mxcl/homebrew#03ed757c, icu4c somehow breaks when being built
with php due to undefined symbols. If being built as an extension,
everything works fine.

Rather than deal with people asking why it doesn't work, I am forcing
the installation of of intl as an extension. A warning will be raised
if the intl flag is passed.

Unfortunately, a post-install dependency isn't straightforward, so at
this time this is the best we can do.

If icu4c becomes compliant with PHP building in the future, we can
revert this change and allow users to rebuild with inline intl support.

Closes #378
Closes #383
Closes #388
Closes #389
tabs to spaces
Build php-cs-fixer.phar on the fly. Closes #377

@fabpot refuses to release tagged builds for php-cs-fixer because it is
pre-alpha software. As such, it is impossible to follow his daily rebuilds
of the released phar, making it a chore to maintain php-cs-fixer.

This commit retools the work by @davidneimeyer in his php-cs-fixer_installer
repo into a homebrew formulae, allowing us to build the phar file on the fly.
Because of the phar requirements, phar.readonly must be set to off for This
formulae to run properly.

Note that detection of installed php bins may fail if you are using HEAD for
your homebrew-php install.
Remove default `ENV.universal_binary` from extensions.

Closes #290
Closes #348
Closes #367
Clarified a debug command
Fix #394: Update php54.rb to PHP 5.4.9
Moved OS X GCC Installer to Super Hack section
Updated warning
Updating php5(3|4)-memcached to version 2.1.0
Fixes for OS 10.5.x Leopard PHP build errors.
PHP Makefile always puts system libraries first

Due to a bug upstream with PHP 5.x (https://bugs.php.net/bug.php?id=44294),
the system libraries are always on the build search path before library
paths passed in the by the user. This causes builds to fail on OS 10.5
Leopard, where many system libraries are out-of-date.

Homebrew OpenSSL required to build PHP5.4 on 10.5.

Due to system OpenSSL being too far out-of-date, PHP 5.4 will not build
without --with-homebrew-openssl installation argument. This commit
defaults that option if MacOS.version == :leopard, otherwise users of
newer versions of MacOS are free to use system or Homebrew OpenSSL as
they desire.
Update PHP_CodeSniffer to 1.4.3.