Teach bayestar_localize_coincs to search multiple paths for PSDs

It is ambigous whether relative paths to gstlal PSD files should be
relative to the directory containing the XML file or relative to the
current working directory. So search both!
13 jobs for bayestar-multiple-psd-paths in 45 minutes (queued for 13 minutes and 35 seconds)
Status Job ID Name Coverage
  Level0
passed #16022
level0:lal

00:03:44

 
  Level1
passed #16023
level1:lalframe

00:01:35

passed #16024
level1:lalmetaio

00:01:30

passed #16025
level1:lalsimulation

00:06:15

passed #16026
level1:lalxml

00:01:05

 
  Level2
passed #16027
level2:lalburst

00:01:42

passed #16028
level2:lalinspiral

00:04:48

passed #16029
level2:lalpulsar

00:03:34

passed #16030
level2:lalstochastic

00:01:36

 
  Level3
passed #16031
level3:laldetchar

00:03:12

passed #16032
level3:lalinference

00:10:32

 
  Level4
passed #16033
level4:lalapps

00:09:45

 
  Container
passed #16034
dockerize

00:06:46