Support erlang 17.2 and 17.3 with kerl
add ssh.github.com known_hosts
Revert "Revert "Invoke perlbrew-installer with bash""

See https://github.com/gugod/App-perlbrew/issues/407

This reverts commit ce3f067b6ad34dfd27c73cccbd7c2185f4ab704a.
Update nvm to v0.17.0
Merge pull request #383 from ljharb/update_to_nvm_0_17_0

Update nvm to v0.17.0
Add PyPy 2.4.0, make it the default
Merge pull request #384 from alex/patch-3

Add PyPy 2.4.0, make it the default
Tweak libstemmer in Sphinx

Fixes https://github.com/travis-ci/travis-ci/issues/2804

Edit libstemmer's Makefile.in so that it can be used while compiling
Sphinx.
This is a bit of a hack, admittedly. It is not quite clear how
we should address this issue long-term when either libstemmer or Sphinx
make changes, but for now, this is good enough to keep things
going.
Update nvm to v0.17.1

Fixes an issue in zsh with some spurious `nvm alias` output.
Merge pull request #385 from ljharb/update_to_nvm_0_17_1

Update nvm to v0.17.1
Remove preinstalled Test::Kwalitee from perl images

See https://github.com/travis-ci/travis-ci/issues/2819
Merge pull request #378 from yoshida-mediba/master

add ssh.github.com known_hosts
Update Go to 1.3.3
Create ramfs data directories

Fixes https://github.com/travis-ci/travis-ci/issues/2514

If /var/ramfs/postgresql exists already, `cp` is not invoked,
leaving /var/ramfs/postgresql/9.3 nonexistent.
Document recent changes
Merge pull request #386 from travis-ci/ha-bug-gh-2514

Create ramfs data directories
Test if /var/ramfs exists before copying data

Some workers (notably Docker images) may not have /var/ramfs
Fix postgresql init file template

* data_dir does not exist by default, so we should check for
the directory above
* prefer '-a' to '&&'
Merge pull request #376 from ericmj/patch-1

Support erlang 17.2 and 17.3 with kerl
Give Eric credit for Erlang updates