Update docs for last endpoint and add test for IPC last endpoint retrieval

Update documentation for last endpoint to mention inaddr_any and add a test for IPC last endpoint checking

More fixes based on CentOS 6.2 results

Tcp get address

Windows build

Needs explicit cast on solaris

Fix build on solaris

Remove thread safe socket code from C API and tests.

Removing old ECANTROUTE documentation

Revert null checks in the API

Adding more specific installation instructions

Minor cleanups

* Fixed use of ssize_t in zmq_msg_t class
* Corrected error after merge, old reference to inner_fctname (broke build)

Return EFAULT if required arguments are null

Renamed scatter/gather methods, cleaned up source

Remove inet_ntop

Compact the trie/mtrie node tables where possible, to reduce memory usag...

Drop subscription messages when reaching the SNDHWM rather than assertin...

Resolve addresses in the calling thread on connect.