Added logog messages to EarClippingTriangulation::initLists().
Handle special case of 3 collinear vertices in ear clipping algorithm.
Reformating in EarClippingTriangulation::initVertexList().
Return nullptr if surface does not consist of any triangles.
Handle the case the surface (triangulated polygon) is a nullptr.
Removed code that outputs triangulation info.
added shapelib if-defs to keep shapelib optional
Merge pull request #160 from TomFischer/FixTriangulationBug

Fix triangulation bug
Update for clang compiler.