Add license/terms of use to the library

Issue #4

I'm using the OpenIB.org license since:
1) I want that everyone will be able to use it and be able to
   continue contributing to it without having licensing problems.
2) Maybe one day, this library will be integrated in the OFED
   Distribution, so having the same license as the rest of the OFED
   components will make it easy (from license prespective).

Signed-off-by: Dotan Barak <dotanb@rdmamojo.com>