Improve Gromacs portability

This patch addresses a few general portability issues
that we have experienced at least on Fujitsu compilers
(K computer) and (partly) for Pathscale x86 compilers.
- I have added a generic compiler definition fallback
  for boost, so it will work on unidentified compilers.
- There is now  a define for gmock-1.7.0 to handle
  the case where wcscasecmp() is not available. We use
  this by default since it is not important for us.
- If we do not find atomics for sparc64 we now warn and
  fall back on mutexes rather than the compile dying.
- The compiler flag checks have been updated from
  cmake-3.0, and more warning checks added.
- Since some non-GCC compilers set _GNUC_ for
  compatibilty, we do not assume all such compilers
  support tr1, but use the internal tr1/tuple definition
  in Gmock by default.
- Before using the sched.h affinity functions, we now
  check that all the functions we need are supported,
  rather than just one of them.

Change-Id: I31b7f0f46a9d03a627c73a0789b4a9b24fa860ee