The main change here is that MPI thread swapping no longer occurs in
 universe_sched.cc. This prevents memory errors in Python.

However, Most of the changes here are due to MiniSSFs svn version being
 different from the version that was downloaded from the website.
Fixed configure checks for pid_t, size_t and ssize_t.
Merge branch 'ssf' of https://github.com/thulas/simx into ssf
- Entity profile generation, changed from div to modulus operator
- Commented out OS-X specific path-append for greenlet
- note that greenlet a dependecy for simx.
- Added sendInfo method to Entity.h that basically does the same checks as the sendInfo
  method in Service.h, and then passes info onto Entity::processOutgoingInfo

- Moved PyInfo sending logic (decision to pickle or not, depending on whether one is using SSF) to
  PyEntity::sendPyInfo (previously located in PyService::sendPyInfo)