Add #includes for OpenBSD

Add includes for <sys/types.h> and <netinet/in.h> to rtp.c and rtsp.c, needed
for the declarations of IPPROTO_TCP, IPV6_V6ONLY, and others.
Define AI_ADDRCONFIG (needed for OpenBSD and NetBSD)

AI_ADDRCONFIG is not supported by some BSDs (OpenBSD and NetBSD).
It's not a critical flag, so define it to 0 just to fix the compile
error.
Merge remote-tracking branch 'abrasive/1.0-dev' into 1.0-dev
Call freeaddrinfo() in rtp.c

Plug a (small) memory leak from getaddrinfo()
Merge pull request #200 from mrpippy/1.0-dev

Compile fixes for OpenBSD, and call freeaddrinfo() in rtp.c