* Removed redundant Z85 code and include files from project
* Simplified use of headers in test cases (now they all just use testutil.hpp)
* Export zmq_z85_encode() and zmq_z85_decode() in API
* Added man pages for these two functions
* disabled the specific tests that do not work (yet) on libzmq
* cleaned up one source (test_spec_rep.c) but the others need similar work
* added sleep in test_spec_rep to allow connects time to happen; this would
not be needed if we connected out to the REP peers instead in from them,
but I didn't want to change the logic of the test code.