Update nodes/php module

The recent release changed the module name
Configure Apt sources to use Ubuntu mirrors

Makes local package downloads much faster
Move Emacs provision into separate class
Improve Puppet provisioning dependencies

Split Python and Ruby installation into separate modules. Make sure that
Ruby and Python are available before installing Gems and Pip packages
respectively.  Also make sure that apt-get sources and indexes are up to
date before installing packages.
Include the Ruby class to provision Gems
Don't require Ruby provisioning on Travis CI
Use side-effect free sorting

Fixes test failures because sorting messed up the option-vars checker
properties.
Expect failures for hdevtools tests

Hdevtools doesn't install with "cabal install" anymore, thus these tests
will fail in either case.
Inhibit readonly while cleaning messages

In Emacs snapshot, *Messages* is read only
Don't change sources.list when provisioning Travis
Refactor selection tests
Clarify notes on supported GNU Emacs versions
Fix expected Go error message on Travis CI
Remove superfluous docstring
Expect failures if checkers are missing

Some syntax checkers fail to install on Travis CI or Vagrant, so we
should expect test failures if the syntax checker is missing, regardless
of the testing environment
Run all tests on Travis CI
Revert "Run all tests on Travis CI"

JRuby and Scala tests still fail on Travis CI, for whatever reason.

This reverts commit 33d81a90a0bbdb331fe34caea569ffdd1f4c32b0.
Update changelog
Remove unused test resources
Fix mocker requirements