Upgrade php to 5.4.31 and 5.5.15
Merge pull request #349 from GrahamCampbell/php

Upgrade php to 5.4.31 and 5.5.15
Install PyPy before PyPy3, and create alias pypy3

See https://github.com/travis-ci/travis-ci/issues/2583

By changing the order, the 'pypy' binary in the pypy-2.3.1 will
be installed as 'pypy' in the default `$PATH`, instead of
that found in pypy3-2.3.1.

We also create a new alias `pypy3` which will point to the
_hard-coded_ PyPy3 binary, so that `tox` users can still use it.
There is a [ticket for PyPy](https://bitbucket.org/pypy/pypy/issue/1796/pypy-pypy3-in-the-same-path)
that will make it unnecessary to do this linking, but until then,
we will need this ugly hack.
Remove PyPy 2.2.1
Install 'wheel' by default for Python runtimes

Fixes https://github.com/travis-ci/travis-ci/issues/2065
Link correct binary
Move symlinking inside the each loop

So that #link is less hard-coded
Merge pull request #351 from travis-ci/ha-bug-ci_2583

Set up PyPy symlinks so that PyPy-2.3.1 is default, and PyPy3-2.3.1 is available as 'pypy3'
Avoid overwriting existing 'pypy3'

If the issue is fixed upstream, we should remove this hack.
Install 5.5.9

On Trusty (14.04 LTS), the default version provided is 5.5.9,
and some users prefer to stick with that version.
Merge pull request #352 from travis-ci/ha-feature-php_5_5_9

Install PHP 5.5.9
Update change logs [skip ci]
Update Android SDK to 23.0.2

Fixes https://github.com/travis-ci/travis-ci/issues/2596
Retain only PHP runtime

To tighten feedback loop while we investigate
https://github.com/travis-ci/travis-ci/issues/2574
Revert "Retain only PHP runtime"

This reverts commit fb80a82308e6ceb7a123982ade226c093f331f7b.

Wrong branch. Sorry.
Add libicu-dev package

Fixes https://github.com/travis-ci/travis-ci/issues/2544
Put back 3.4.0

This was requested by a customer.
Please do not remove this unless it is cleared from the customer.
Leiningen 2.4.3

This version will use HTTPS when fetching stuff from Maven Central => big deal.
Merge pull request #355 from michaelklishin/patch-4

Leiningen 2.4.3
Add default .gitconfig with empty core.pager

When user calls git command that may invoke pager, it may hang
the build if input is expected.

Fixes https://github.com/travis-ci/travis-ci/issues/2651