Merge pull request #5 from hintjens/master

Added autoconf packaging
Implement zmtp_dealer_tcp_connect function
Merge pull request #6 from hurtonm/master

Implement zmtp_dealer_tcp_connect function
Simplify IPC connect function
Merge pull request #7 from hurtonm/master

Simplify IPC connect function
Various project cleanups

- added zmtp_prelude.h (similar to czmq_prelude.h)
- added selftest methods for all classes, still empty
- added comment headers for all methods (not finished)
- added tags for man pages in public header files
- simplified error handling for memory exhaustion (asserts :-)