add Dimension constant to Face class
add two constants to TemplateQuad (the number of all nodes, the number of base nodes)
test constants of Quad element
Renamed attributes in Face and TemplateQuad according to style guide.
Accessing dim and num of nodes via methods too.
Made test name more meaningful.
Added constants tests for quad8 and quad9 elem types.
Changes due to rebasing to recent master.
Removed the underscore in static variables in Face and TemplateQuad as requested by Karsten.
Added typedefs for Quad8 and Quad9.
Removed unnecessary includes.
fix compiler warnings due to comparison of signed and unsigned
fixed index error in GeoTreeItem where name changes to surfaces would result in a crash when the geometry did not contain polylines
Merge branch 'master' of https://github.com/ufz/ogs into GeoTreeModelBugFix
Merge pull request #226 from rinkk/GeoTreeModelBugFix

Geo tree model bug fix
Merge pull request #224 from norihiro-w/fix-warnings

Fix compiler warnings due to comparison of signed and unsigned
Merge pull request #198 from norihiro-w/add-element-static-functions

Add constants to mesh element classes
replaced nearest neighbour technique with triangle-line-intersection for mapping of geometry on mesh
moved collision detection methods to AnalyticalGeometry, added fixes based on pull request comments
Merge pull request #228 from rinkk/TriangleLineIntersection

Geometry on mesh mapping via Triangle-Line-Intersection