Merge pull request #8 from thinkthroughmath/events_support

Events support
bump 0.0.3
Merge branch 'master' of github.com:Clever/clever-ruby
bump 0.0.4
Expose event.previous_attributes
Fix a reference to the no-longer-existing @@api_base; instead use configuration.api_base.
Require all the error classes
Merge remote-tracking branch 'origin/master'