Replace most uses of Map by HashMap

* Map is unnecessary and inefficient in almost every case.
* Replaced by the new HashMap.
* Renamed Map to RBMap and Set to RBSet for cases that still make sense
  (order matters) but use is discouraged.

There were very few cases where replacing by HashMap was undesired because
keeping the key order was intended.
I tried to keep those (as RBMap) as much as possible, but might have missed
some. Review appreciated!

thirdparty/misc/polypartition.h

@@ -26,7 +26,7 @@
 
 #include "core/math/vector2.h"
 #include "core/templates/list.h"
-#include "core/templates/set.h"
+#include "core/templates/rb_set.h"
 
 typedef double tppl_float;
 
@@ -224,8 +224,8 @@ public:
   // Helper functions for MonotonePartition.
   bool Below(TPPLPoint &p1, TPPLPoint &p2);
   void AddDiagonal(MonotoneVertex *vertices, long *numvertices, long index1, long index2,
-          TPPLVertexType *vertextypes, Set<ScanLineEdge>::Element **edgeTreeIterators,
-          Set<ScanLineEdge> *edgeTree, long *helpers);
+	  TPPLVertexType *vertextypes, RBSet<ScanLineEdge>::Element **edgeTreeIterators,
+	  RBSet<ScanLineEdge> *edgeTree, long *helpers);
 
   // Triangulates a monotone polygon, used in Triangulate_MONO.
   int TriangulateMonotone(TPPLPoly *inPoly, TPPLPolyList *triangles);