Touch up README.md
Add the badges to README

Closes #2 #4 #5

Enables Coveralls in RSpec spec_helper.rb.
Enable Rubocop for Rakefile

Make Rakefile adhere to Rubocop style.
Merge branch 'badges' into development
Fix Bundler fallacy of ignoring Gemfile.lock
Remove Gemfile.lock line
Add installation guide
Add CONTRIBUTING.md
Fix < and > characters in Usage paragraph
Publish the gem at RubyGems.org

* Add the version badge to README.md