Add love.data module.

- Moved love.math.compress / decompress / decode / encode / hash to love.data.
- Changed love.data.compress/decompress to take the format argument first instead of second.
- Added love.data.newDataView. Returns a read-only subsection of an existing Data object.
- Added love.data.newByteData. Mostly useful in combination with LuaJIT's FFI as it has no extra methods currently.
- Added implementations of Lua 5.3's data packing APIs: love.data.packString / packData / unpack / getPackedSize.

Resolves issue #1336.
Resolves issue #1331.

--HG--
branch : minor

src/modules/filesystem/wrap_Filesystem.cpp

@@ -24,7 +24,7 @@
 #include "wrap_File.h"
 #include "wrap_DroppedFile.h"
 #include "wrap_FileData.h"
-#include "common/wrap_Data.h"
+#include "data/wrap_Data.h"
 
 #include "physfs/Filesystem.h"
 
@@ -233,7 +233,7 @@ Data *luax_getdata(lua_State *L, int idx)
 	}
 	else if (luax_istype(L, idx, Data::type))
 	{
-		data = luax_checkdata(L, idx);
+		data = data::luax_checkdata(L, idx);
 		data->retain();
 	}