Created the loadGameMap() function, still incomplete

Although the overall logic of this function is finished, I still need to
write the callbacks for RegionPager's onNew and onDelete.

I've also tested this using a hand written save/index file. I've written
up a map file format by hand, and I'll be implementing it over the next
few commits.

common/map_loader.hpp

@@ -0,0 +1,15 @@
+#ifndef MAPLOADER_HPP_
+#define MAPLOADER_HPP_
+
+#include "region_pager.hpp"
+#include "tile_sheet.hpp"
+
+#include <list>
+#include <string>
+
+/* Given the map name and pointers to containers, this is a generic loading system
+*/
+void loadGameMap(std::string mapPathName, RegionPager* pager, std::list<TileSheet>* sheetList);
+void saveGameMap(std::string mapPathName, RegionPager* pager, std::list<TileSheet>* sheetList);
+
+#endif