Fixed over 500 compile warnings. Mostly:

* Unused variables.
* Missing newlines at ends of #included files.
* signed int loop variables where the termination condition is an unsigned 'get number of' function.
* 'NULL' used inappropriately for an integer or character constant (NULL is a pointer)
* abstract base classes with no virtual destructor.
* Floating point constants used to initialise integer variables.

Extras/ConvexDecomposition/splitplane.cpp

@@ -185,9 +185,6 @@ bool computeSplitPlane(unsigned int vcount,
                        ConvexDecompInterface *callback,
                        float *plane)
 {
-  bool cret = false;
-
-
   float bmin[3] = { 1e9, 1e9, 1e9 };
   float bmax[3] = { -1e9, -1e9, -1e9 };