Add Bananaphone transport to obfsproxy

The Bananaphone transport needs tor#10243 to be completed: https://trac.torproject.org/projects/tor/ticket/10243#ticket

After that happens then we can test and then merge the Bananaphone transport. Right now these tor#10243 related changes are here:

https://github.com/david415/obfsproxy/tree/david-bananaphone-public-options

Trac:
Username: david