[MathLib] PETScMatrix style.
Fix warnings in tests.
fixed normal vector for surface extraction (was overlooked when changing node numbering a few months ago)
Merge pull request #409 from TomFischer/FixWarnings

Fix warnings and docu improvement.
Added hipchat and removed campfire token.
[FileIO] Implemented getMeshDensityAtStations().
[FileIO] Using station mesh density at station points.
[GMSHPolygonTree] Removed method declarations with missing implementation.
[GMSH] Made docu more specific.
Substituted size_t with std::size_t.
[GMSHPolygonTree] Reduced indentation in insertPolyline().
[PointVec] Documented private method uniqueInsert().
[GMSH] Moved inserting the Polyline to the end of the method.

Before inserting the new polyline, there should be some tests performed with the already existing polylines.
[GMSH] Reformating for readability.
[GMSH] Added GMSHPolygonTree::checkIntersectionsSegmentExistingPolylines().
[GMSH] Included AnalyticalGeometry.h into GMSHPolygonTree.
[FileIO] GMSHInterface::writeGMSHInputFile() Copy stations.
[GeoLib] SimolePolygonTree: docu + style.
[GeoLib] Test for createPolygonTrees().
[GeoLib] Fix bug in createPolygonTrees().