Determine Feasability of Including High-Perf Message Functions

[pblasucci]

Determine if the (few) unimplemented high-performance message functions can be implemented with reasonably close-to-native speed. Specific functions are:

• zmq_msg_init_data
• zmq_msg_move
• zmq_msg_copy
• zmq_send_const

[pblasucci]

zmq_msg_move and zmq_msg_copy have been implemented, though performance metrics (and general stability tests) remain inconclusive. They've been labelled experimental (i.e. may be removed at a future date), and should be handled with care. zmq_msg_init_data and zmq_send_const have not been implemented, as their use is generally only applicable in scenarios outside the scope of fszmq.