While there, fix some whitespace issues.

Linux uses in some cases only enums, so one can't check with #ifdef.

For now don't allocate memory, so we don't have to free it.
This will not work for all future socket options, but it simplifies
things for now.

Merge I-DATA support.

This fixes #25, #27, and #29.

Added interrupt handler to run.c for handling interrupt signals

This patch allows to use sctp_assoc_value in getsockopt and also supports
numeric constants as values.