Renamed item.fileSize to item.size in fs.list() return value, enabled 3D in the editor, added a lot of missing documentation

For the return values, I followed this rule: if the fuction returns true on success, it should return false, error on error; for every other case it should return nil, error on error.

Also, who doesn't want to edit code in 3D ? The line depth depends on the indentation level.

source/cam.c

@@ -21,6 +21,9 @@ The `cam` module.
 /***
 Initialize the camera module.
 @function init
+@treturn[1] boolean `true` if everything went fine
+@treturn[2] boolean `false` in case of error
+@treturn[2] integer error code
 */
 static int cam_init(lua_State *L) {
 	Result ret = camInit();