CSS scheduling - Githubissues

This PR adds lots of functionality related to scheduling the CSS telescope, including

calculating the probability for each CSS field in the GW skymap
selecting the more probable fields and checking their observability
submitting the fields to the CSS computer
calculating the localization credibility region contours and storing them in the database
adding the Aladin skymap to visualize the CSS fields, sun, moon, and candidates on top of the localization
running all of this code on "external coincidence" maps as well as the GW-only skymaps

SAGUARO-MMA / saguaro_tom