No need to use the _internalQueue to sync the stateMachine
Use attr.name as the key in the attributes dictionary. Tidied up JRProperty a bit more.
Added category-level support for spinning a runloop predicated on a JRStateMachine's state.
Upon initialization, a state transition shouldn't have any nil states.
Use the new runloop support from JRStateMachine in unit tests.
Fleshing out JRMethod