Ligo skymap
The purpose of this MR is to add the ability to use the ligo.skymap package if it is installed. Note that if it is not installed, then the default PESummary skymap should be used.
Edited by Charlie Hoy
The purpose of this MR is to add the ability to use the ligo.skymap package if it is installed. Note that if it is not installed, then the default PESummary skymap should be used.