Changes to get PoissonRecon plugin compiling on Mac OS X:
  - rename Time.h
  - remove extra template specialization
  - move definitions of specialized static members out of headers

Changes to PoissonReconLib.cpp:
  - typedef typename in template since not inherited
  - add “this” pointer to member vars
Merge pull request #118 from asmaloney/poisson_changes

Changes to get PoissonRecon plugin compiling on Mac OS X