adjusted BVH
improved 2D/3D BVH
new bounding volumes
new test cases
renamed some test-cases for grouping reasons
made GPC header-only using slight adjustments
added corresponding test-cases
switched to newer version of tinyxml due to some issues
adjusted affected code-parts accordingly
for better re-use, moved ceiling-calculation to a new class
some minor fixes
new helper methods
worked on wifi-opt