add ssh.github.com known_hosts
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 '&&'