Update the way ruby versions are defined with rvm

* https://rvm.io/workflow/projects#ruby-versions
* http://stackoverflow.com/questions/15708916/use-rvmrc-or-ruby-version-file-to-set-a-project-gemset-with-rvm
Update Gemfile.lock
Update date in changelog
Remove space in JS file
Merge pull request #2 from christianv/small-update

Small update
Merge pull request #1 from christianv/rvm-update

Update the way ruby versions are defined with rvm
Add a ruby gem version badge
Merge pull request #3 from christianv/add-badge

Add a ruby gem version badge
Remove DS_Store file
Add .DS_Store to gitignore
Add editorconfig
v3.0.2 Release
Add update script