Remove *.gxx files from Mesh algorithm

Documentation remark, added by Commenter 2 2011-02-21 15:34:38:

New features:
No
Improvements:
As generic structures from MeshAlgo and MeshDS packages are used in BRepMesh
package only they have been moved to BRepMesh and became a concrete
interpretations.
Changes:
MeshDS and MeshAlgo packages have been fully removed and all of their structures
have been moved to BRepMesh package. So the generic classes became a concrete
implementations now, because genericity is not necessary here. Names of
structures were changing in respect to existing aliases in BRepMesh.

Modified entities:
MeshDS, MeshAlgo packages: deleted;

BRepMesh package:
New files moved from MeshDS, MeshAlgo and renamed in accordance to existing
aliases: BRepMesh_CircleTool (BRepMesh_CircleTool.cdl),
BRepMesh_ComparatorOfIndexedVertexOfDelaun
(BRepMesh_ComparatorOfIndexedVertexOfDelaun.cdl),
BRepMesh_ComparatorOfVertexOfDelaun (BRepMesh_ComparatorOfVertexOfDelaun.cdl),
BRepMesh_DataStructureOfDelaun (BRepMesh_DataStructureOfDelaun.cdl),
BRepMesh_Delaun (BRepMesh_Delaun.cdl), BRepMesh_SelectorOfDataStructureOfDelaun
(BRepMesh_SelectorOfDataStructureOfDelaun.cdl), BRepMesh_Circ
(BRepMesh_Circ.cdl);

Header files for importing:
BRepMesh_MapOfInteger.hxx, BRepMesh_MapOfIntegerInteger.hxx,
BRepMesh_CellFilter.hxx, BRepMesh_CircleInspector.hxx,
BRepMesh_ListOfInteger.hxx, BRepMesh_PairOfIndex.hxx,
BRepMesh_BaseAllocator.hxx;

Declaration of enumeration DegreeOfFreedom was migrating to BRepMesh.cdl;