Update changelog and add structure

  * renamed CHANGES.md to CHANGELOG.md
  * move changes from README.md to CHANGELOG.md
  * add structure that follows http://keepachangelog.com/
remove unnecessary headings from changelog
Merge pull request #79 from pxlpnk/update_changelog

Update changelog and add structure
ship MIT license with the Gem
cleanup gemspec

this is based in the changes @grosser proposed
Merge pull request #80 from pxlpnk/add_license

Add license + cleanup gemspec
adds rubocop and ci raketask for the future
Rubocop autocorrect
remove rubyforge from gemspec
Merge pull request #81 from pxlpnk/add_rubocop

Add rubocop, use rubocop autocorrect and retire rubyforge from gemspec ✞
Update README.md

It took me a while to make the connection between 

    payload[:host] = request.host

in the controller and

    event.payload[:host]

in the custom_options lambda. This or something like it should make it a little more clear.
Resolves formatting issues
Merge pull request #82 from roidrage/patch-1

README patch to clarify `custom_options` usage.
Adds a formatter for the lines format