PAstro gracedb upload refactors
See the most recent commit message:
"Make gracedb upload handling consistent
Use deff list instead of getattr
rename trigger to postcoh_inspiral"
PAstro had slightly different loops/messages to our other 2 gracedb uploads, so I tried to take the best of each and use it consistently throughout. It Could be a standalone function that takes a lambda or something, but I don't think it's worth it at this stage.
I'm unsure of the best testing strategy for gracedb uploads.