Merge pull request #755 from hintjens/master

Added links to RFCs for socket patterns
Fixed typo in documentation about zmq_proxy_steerable()
Merge pull request #756 from 0x6d686b/master

Fixed typo in documentation about zmq_proxy_steerable()
Fixed test_many_sockets

* failed on systems where process could not allocate 1024 sockets by default
* include path for platform.hpp was wrong; fixed it