usrsctp-neat needs merge with upstream changes from sctplab/usrsctp

[dreibh]

usrsctp-neat needs merge with upstream changes from sctplab/usrsctp.

[lgrahl]

Ping. This is also needed for rawrtc/rawrtc#68.

[tuexen]

This fork is maintained by @ruengeler, so I'm assigning it to her. But she is on vacation right now...