Adding release checksum.

Signing v0.4.0

Added tag v0.4.0 for changeset ff8ee9d1b81b

Bump the minor version, update history.

Allow the State event callback to accept additional arguments.

Report operator arguments in the spec matcher failure output.

Allow additional args when specifying the #on_event op in the transition matcher.

Adding release checksum.

Signing v0.3.0

Added tag v0.3.0 for changeset afa03e587fd6

Bump the minor version, update history.

Rework how state data is passed around.

Instead of passing it through the transition callbacks, which proved to be a terrible idea, the
States themselves take an optional state argument to their constructor.

Fix the license file

Adding release checksum.

Signing v0.2.0

Added tag v0.2.0 for changeset b584f193d110

Update manifest

Bump the minor version, update history.

Add spec helpers with a transition matcher.

Fix header of spec files