[BUILD] added git support to build system
[BUILD] small fix in git version extraction
[BUILD] added git version information to VersionInfo / OpenMSInfo
[BUILD,NOP] added missing mac osx version to OpenMSInfo
[FIX-#861,DOC] fixed eigen 3.2.1 problems with GammaDistributionFitter

 * redefined gamma distribution to be 0.0 if parameters are <= 0.0, while this
   violated basic assumptions on statistical distributions it allows the usage of
   an unconstrained optimisation algorithm (like eigen's lm)
 * assigned myself as maintainer
 * updated documentation
 * fixed error in GAMMA_DISTRIBUTION_FITTER_VERBOSE code path
[NOP] add revision number (if available) also to the GUI About dialogs
Merge pull request #866 from aiche/feature/git-version-embedding

[FEATURE] git version embedding
Merge pull request #867 from aiche/fix/gamma-distribution-fitter-eigen3.2.1

[FIX-#861,DOC] fixed eigen 3.2.1 problems with GammaDistributionFitter