Isolate JKRHeap operator overloads

Fixes #25

This isolates the JKRHeap operator new/delete overloads. Every single new/delete site in the code has been replaced with a macro.

Sadly for new[] and delete[] we have to keep global operators. The global new[] just allocates into malloc() however, and delete[] goes into free() if it's not in a JKRHeap. So that's fine.

src/d/d_map_path_dmap.cpp

@@ -384,7 +384,7 @@ int dMpath_c::getTopBottomFloorNo(s8* i_topFloorNo, s8* i_bottomFloorNo) {
 }
 
 void dMpath_c::createWork() {
-    mLayerList = new dDrawPath_c::layer_data;
+    mLayerList = JKR_NEW dDrawPath_c::layer_data;
     JUT_ASSERT(1416, mLayerList!=NULL);
 }