Ressurect move.cpp

Actually it is san.cpp renamed. Because now has the move
conversions functions and doesn't have any more the bulky
move_from_san(), it is better to call it move.cpp

Remove san.h while there.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>

src/search.cpp

@@ -34,10 +34,10 @@
 #include "evaluate.h"
 #include "history.h"
 #include "misc.h"
+#include "move.h"
 #include "movegen.h"
 #include "movepick.h"
 #include "lock.h"
-#include "san.h"
 #include "search.h"
 #include "timeman.h"
 #include "thread.h"