Merge pull request #3 from underrun/master

remove need for specification of stop/wait type
add a crude check for a custom exception message in the test suite
prepare for 1.2.0 release
update HISTORY.rst for 1.2.0 release
Fix AttributeError when explicitly specifying wait type, and add appropriate regression tests. (fixes #4)
Merge pull request #5 from alexkuang/master

Fix AttributeError when explicitly specifying wait type ...
update HISTORY.rst, bump version up to 1.2.1 for release
bump version up to 1.2.2-dev