(svn r1751) - Feature: New PathFinder (NPF).

- Supports trains, road vehicles and ships.
	- Uses A* pathfinding (same codebase as the new ai).
	- Currently unlimited search depth, so might perform badly on large maps/networks (especially ships).
	- Will always find a route if there is one.
	- Allows custom penalties for obstacles to be set in openttd.cfg (npf_ values).
	- With NPF enabled, ships can have orders that are very far apart. Be careful, this will break (ships get lost) when the old pathfinder is used again.
- Feature: Disabling 90 degree turns for trains and ships.
	- Requires NPF to be enabled.
	- Ships and trains can no longer make weird 90 degree turns on tile borders.
- Codechange: Removed table/directions.h.
	- table/directions.h contained ugly static tables but was included more than once. The tables, along with a few new ones are in npf.[ch] now. Better suggestions for a location?
- Fix: Binary heap in queue.c did not allocate enough space, resulting in a segfault.
- Codechange: Rewritten FindFirstBit2x64, added KillFirstBit2x64.
- Codechange: Introduced constant INVALID_TILE, to replace the usage of 0 as an invalid tile. Also replaces TILE_WRAPPED.
- Codechange: Moved TileAddWrap() to map.[ch] 
- Add TileIndexDiffCByDir(), TileIndexDiffCByDir(). 
- Codechange: Moved IsTrainStationTile() to station.h
- Add: IsRoadStationTile() and GetRoadStationDir().

queue.c

@@ -420,7 +420,7 @@ void init_BinaryHeap(Queue* q, uint max_size)
 	q->data.binaryheap.size = 0;
 	// We malloc memory in block of BINARY_HEAP_BLOCKSIZE
 	//   It autosizes when it runs out of memory
-	q->data.binaryheap.elements = calloc(1, ((max_size - 1) / BINARY_HEAP_BLOCKSIZE) + 1);
+	q->data.binaryheap.elements = calloc(1, ((max_size - 1) / BINARY_HEAP_BLOCKSIZE*sizeof(BinaryHeapNode)) + 1);
 	q->data.binaryheap.elements[0] = malloc(BINARY_HEAP_BLOCKSIZE * sizeof(BinaryHeapNode));
 	q->data.binaryheap.blocks = 1;
 	q->freeq = false;