Put tiled rasters in catalog

The format for tiled rasters has changed a bit. Instead of one directory, with a layout.json being the metadata and all the tiled args along side of it, it's now an independant metadata JSON file of the same format as layout.json. In that JSON you have the option for a "path" field that will point to the directory with the tile args. If you leave that out, it defaults to a directory in the same parent directory as the metadata file, with the name of the layer. So basically layout.json is pulled one directory higher, and you can name it whatever you want as long as you specify the 'path' argument.

Some Todo's off of this request:
- Be able to convert tiled rasters
- Write tiled rasters in the new format.