calling desi modules in tilepicker.py

This has been seriously attempetd but we need to verify desi modules can be easilt called in within tilepicker.py

I had a faulty python setting on which running JS/bokeh would rock the boat on the desi modules. Just need to make sure we can use desimodules here if we needed.

One good/easy test: see if desimodel.focalplane.get_tile_radius_deg() can be called here so that we can show the tile markers to be the exact angular size of the tiles.