Tweak Aruba config for jRuby.

Tested with jruby-1.7.9, also add global @announce-cmd because it can
be tweaked to run quicker without cmd spawning a new Ruby process.
Merge pull request #153 from futhr/feature/tweak-aruba-jruby

Tweak Aruba config for jRuby.
Fixes install --github so it append README.md

- Before it replaced the README.md file with new content, now its
append content in a more proper manner. If no README.md exists its
still created.
- .localeapp was sometimes injected without space on the previous
.gitignore key, now it ensure newline.
Merge branch 'feature/append-readme' of github.com:futhr/localeapp into feature/append-readme