BUILDEM_ENV_STRING: Add CC and CXX environment variables, based on CMAKE compiler vars.
Merge branch 'master' of ssh://github.com/stuarteberg/buildem
Merge branch 'master' of https://github.com/janelia-flyem/buildem
vtk.cmake: Added explicit search path to linker flags.
opengm: Added a patch to let us skip the sphinx docs build with a cmake switch.
qt4.cmake: Don't build accessibility module, since causes build issues on Ubuntu.
Merge pull request #29 from chaubold/fix/psutil

Update psutil from 0.6.1 to 2.1.1
vigra.cmake: On Mac, use -DWITH_BOOST_THREAD.  Also, updated default version to today's master.
Merge remote-tracking branch 'upstream/master' into fix/OSX10.9