Here are all the source files for nanomsgxx, the file names match the ones of
nanomsg, for example C++ ports of symbols in nanomsg/nn.h will be found in
nnxx/nn.h, etc...
This C++ port also add some more abstractions that take advantage of C++11 new
features and make the code easier to use, these are available in extra header
files that don't match any in the C nanomsg API.
