Add support for extra condor options

This MR adds support for providing additional condor arguments to pygwb that will be added to the relevant submit files. The syntax for adding these options is either providing the options to all jobs in the [condor] section, or for a specific job type in the [condor-JOB_TYPE] section. For example, the following would be valid sections:

[condor]
universe = vanilla

[condor-pygwb_pipe]
environment = GWDATAFIND_SERVER

In the above example, the line universe = vanilla would be added to every submit file, while the line environment = GWDATAFIND_SERVER would be added to only pygwb_pipe jobs.