Add more help.
Add :_cleanup_ event which is fired on :_exit_ to give client application a chance to tidy up before the application terminates.
Add yard development dependency.
Add Yard documentation around API methods.
Update with more help, development and contribution information.
Improve help/documentation.
Add some return types to API documentation.
Merge pull request #78 from gavinlaking/twerks

Generally improving documentation.