0.34

This is a bug fix release that addresses some minor build issues and a
bug in lo_server_recv() for short-lived TCP streams.

Changes of note since the 0.33 release include:

• Fixed lo_server_recv to loop again if partial message is received.
• Added --enable-doc option, otherwise error if docs not built.
• Fixed test_bidirectional_tcp to avoid use of sleep.
• Updated docs to discourage use of lo_server_recv.