added callback functionality to async
unwired callbacks on unwatch, added timestamps
simplified callback checking
added Windows port support
Merge branch 'async' of http://github.com/brendanwhitfield/python-OBD into async
fixed threading problem with command dict resizing during iteration
switched class name from OBD to Obd
decided against the name change, its an acronym, it should stay caps
allow for multiple callbacks per command
calling unwatch can have the affect of only removing the callback
made unit types more consistant and more useful
bump to 0.2.0
linked to the wiki in the readme
fixed capitalization error in command names
Merge pull request #1 from brendanwhitfield/master

Merge from brenanwhitfield