Created calling/raises matcher
Fixed <2.6 compliant exception handling
Renaming DelayedCall, with_ and removing initial arg passing to DefferedCallable
Fixed NoneType cornercase is is_callable
Weakref now maintained by Raises to previously matched item
Moved is_callable to a generic compat.py
Adding calling/raises to the tutorial documentation
Merge remote-tracking branch 'perfa/feature_raises_matcher'

Resolves #30
Small reformatting of the doc for calling/raises
Bump version to 1.8.0 alpha
Track PyPi release status