Update default condor environment and remove getenv

This MR updates the default condor environment options for dags, with the primary change being the removal of getenv from submit files. All of these settings can be overridden by specifying desired values in the analysis configuration file. This is a follow-up to !565 (merged)

The changes to the config class are:

• Remove HAS_SINGULARITY as a requirement for jobs, since this matches all nodes on CIT, PSU, and UWM. This also allows removal of a fixme in the online makefile.
• Do not set getenv by default, allowing it to fall back to the default value of False.
• Change the SINGULARITY_PWD environment variable to initialdir, which is functionally identical, but acts at the condor level instead of in singularity.
• Make the proxy and file transfer options independent of the singularity option.

The LAL_DATA_PATH in the site profiles is also updated from oasis.opensciencegrid.org to the new and preferred software.igwn.org