Make target to generate documentation using doxygen
Use platform-dependent gmsh library name
Use platform specific paths to detect vtk headers and libs
By default build only gcm3d binary
Reworked Node and CalcNode classes
API to set/get values of custom flags in CalcNode
Merge branch 'master' into refactoring

Conflicts:
	src/libgcm/mesh/tetr/TetrMeshSecondOrder.cpp
WA to make contact conditions work again
Revert "WA to make contact conditions work again"

This reverts commit dc38b4143c190ddc1cc5336a877d010836495082.
Update func tests structure
Add drawing graphs for func tests
Further upgrading tests:
- Check along arbitrary line
- Produce graphs with the same yrange for all steps
- Add interpolateNode(CalcNode&) API, implement it for tetr meshes
- Use new API in tests, make tests mesh type independent
Disable gmsh messages on stdout - there is no point in them since they do not go into log file
Unified rheology-independent APIs
Merge remote-tracking branch 'origin/master'

Conflicts:
	src/tests/func/PWavePropagation.cpp
	src/tests/func/SWavePropagation.cpp
Removed make-based waf wrapper
Replaced initializer_list with vector
Handle implicit dependencies in Makefile correctly