Task #93: mesh nodes index redesigned for better performance

 Changes to be committed:
	modified:   .gitignore
		Ignore rotated log files
	modified:   gcm/meshtypes/TetrMesh.cpp
	modified:   gcm/meshtypes/TetrMesh.h
		Nodes index redesigned
	modified:   gcm/meshtypes/TetrMesh_1stOrder.cpp
		New profiled sections
TetrMesh::findOwnerTetr optimization

 Changes to be committed:
	modified:   gcm/meshtypes/TetrMesh.cpp
	modified:   gcm/meshtypes/TetrMesh.h
	modified:   gcm/meshtypes/TetrMesh_1stOrder.cpp
	modified:   gcm/meshtypes/TetrMesh_1stOrder.h
		Added method to findClosest node to the specified point by a known nearby node, found node is then used to find a tetrahedron containing specified point.
Task #119: Ability to specify collision detector to be used in model
description file

 Changes to be committed:
	modified:   gcm/system/BruteforceCollisionDetector.cpp
	modified:   gcm/system/BruteforceCollisionDetector.h
	modified:   gcm/system/CollisionDetector.h
	modified:   gcm/system/CollisionDetectorForLayers.cpp
	modified:   gcm/system/CollisionDetectorForLayers.h
	modified:   gcm/system/VoidCollisionDetector.cpp
	modified:   gcm/system/VoidCollisionDetector.h
		Add and implement virtual method getName returning
detector name that can be used to specify it in model description
Task #75: ability to specify mesh element size when mesh is automatically generated using a geo script

 Changes to be committed:
	modified:   gcm/meshtypes/TetrMesh_1stOrder.cpp
		Modify method loadGeoScriptFile to retrieve mesh element characteristic size from input parameters by key "tetrSize" and feed it to Gmsh