otlib: Removing OpenSSL from header files
otlib: OTCachedkey.cpp, added opemssl lib for thread-check
Fixes "WARNING: OpenSSL was NOT compiled with thread support.  (Master Key will not expire.)"
Merge pull request #120 from lclc/ssl2

otlib: Removing OpenSSL from header files
compile but don't use zmq
make zmq4 optional
make zmq4 the default