~Removed some warnings about convertion from

 to float

+Add: some functionality to the building algorithm
~Rename: kd tree building classes
+Add: MathUtils, which contains some methods to compute ==, <, > with
 a range of error epsilon
Merge branch 'fastkdtree-SS13-group1' of https://github.com/happah-graphics/happah into fastkdtree

Conflicts:
	happah/testmain.cpp