added functionality for displaying mesh information
removed unnecessary files from cmake
integrated mesh information view into GUI, added docu and cleaned up
added mesh source initalisation again
changes based on PR comments, moved mesh detail extraction to new MeshInformation class
changed getMatBounds() to getValueBounds(), changed copies of bounding box points to references
changes element types parameter to return value
added element type initialisation
added signal such that treeview is automatically expanded
added newlines at eof
changed all kinds of pointers and copies to references
Merge pull request #248 from rinkk/MeshInfoView

Mesh Information View in GUI