Made better checking for errors when msg == NULL.
Fix README.rst inline code formatting.
Added Makefile.
tlv_object.c: Fixed bugs with send/recv API.

Now these are tested (by way of an application that uses it) and
working. If you want to see these in action, check this project:

	https://github.com/jpmelos/gossip-node

and this one (a server for the nodes of the first one):

	https://github.com/jpmelos/gossip-server