Added ruby 2.1.2.
Varies tweaks

- Updated to Ubuntu 14.04
- Added sqlite
- Updated Vagrantfile to use APIv2
- Added a Dockerfile step to add ssh keys
Corrected ubuntu package in README [ci skip]
Updated docker install instructions [ci skip]
Added memcached
Merge pull request #6 from fredwu/trusty64

Varies tweaks
Tweaked the README