add FeLINE2 and FeHEX8
add tests for FeLINE2 and FeHEX8
remove loops and reuse computed values
adjusted existing classes to new DuplicateMeshComponent methods
removed unnecessary includes
changed signatures to return the number of found elements
adjusted utility for mesh element removal to use ElementExtraction class
Fixed warning: unused variable ‘node_id’.
Removed unused code in TestTriLineMesh.
Remov more warnings when g++ is used
recovery two files that are corrected in one PR by Tom
initialize with zero in ShapeMatrices constructor
merge coordinates mapping tests for different element types to one test
add tests for checking field specifications
merge tests for Fe types to one
test different fe types and different matrix types
Merge pull request #8 from TomFischer/InconsistentMeshFix

Fix two warnings.
fixed two more warnings
Merge pull request #386 from rinkk/InconsistentMeshFix

Removal of duplicate code in MeshLib
fix clang compiling errors