Merge remote-tracking branch 'KazakovBranch/master'
Merge remote-tracking branch 'upstream/master'
Added support for external material libraries
Merge remote-tracking branch 'upstream/master'
Reworked tests (especially perf)
Changed include paths for launcher and tests to src-relative ones (e.g. libgcm/...)
Merge remote-tracking branch 'upstream/master'
Use python2 as default interpreter
Add configure options to corresponding group
Look for vtk libs and headers also in folders vtk-*
Added build variants support and reworked configuration options a bit.
Do not compile the same file multiple times if it's used to produce
different binaries
Removed unused configuration flags and waftools/utils.py module.
Use templated singleton class for Engine implementation
Do not manage MPI state inside libgcm
Do not forward arguments in Singleton::getInstance
Refactored geo2 mesh loader: devided code between libgcm and launcher
Improved xml APIs
Removed loaders for first order meshes since these loaders are broken
Use relative to src include path in libgcm