Uncrustify.
Extract common part of DataArrangement tests into a fixture.

Also remove created objects cleanly. Remove all memory leaks from this test.
In VecMatOnMeshLib/TestSerial* initialize global matrix with zeros.
In VecMatOnMeshLib/TestSerial* remove memory leak.

vec_comp_dis was not released.
Add LocalToGlobalIndexMap packing indices for rows or columns.
Rewrite global assemblers for using of LocalToGlobalIndexMap.
Generalize 2d diffusion to arbitrary mesh size.
Remove unused #includes.
Remove IVecMatOnMesh--no dynamic polymorphism.
Rename SerialVecMatOnMesh to SerialVectorMatrixBuilder.
Make SerialVectorMatrixBuilder a template over matrix/vector types.

Also define types using Dense, CRS, and Lis linear algebra objects.
Add finalizeMatrixAssembly call in TestSerialLinearSolver.
Rename mesh_item_comp_ID and comp_ID.

New names are ByLocationAndComponent and ByComponent.
In SerialLinearSolver test rewrite outer loop in ele -> node build.
Replace OrderingType type by enum class ComponentOrder.

This enum is used only in MeshComponentMap.h---no extra file needed.
Split getDataIDList() for vectors into two templated specializations.

Each of the new functions is more efficient than the previous implementation.
WIP.