Added MPI_Actor_get_num routine.
Added beginnings of MPI_Actor_start routine.
Fixed test/actor_start.test.c to use correct communicator in test calls.
Tweaked interfaces so actor_main doesn't receive message data. It should instead use a "hear" function. Added an interface to get the main function from the actor_type.
Added error return checking to test/type_create_actor.test.c
Added call to MPI error handler in MPI_Actor_get_data function.
Changed MPI_Actor_main_function interface.
Updated test/actor_start.test.c to follow new actor main prototype.
Added more MPI_Actor_get_main tests.
Added some basic actor instance definition, creation and destruction functions to src/actor_start.c
Poked at interface.
Further poked design interface.
Updated interfaces to match changes in interfaces.txt.
Added requirement for receptionist to message self to run twice.
Merge branch 'add-actor-start' of https://github.com/poconbhui/mpi-actor-c into add-actor-start

Conflicts:
	src/actor_start.c
	test/actor_create.test.c
	test/actor_start.test.c