Implement support for pulling outages from `nerc-rates`

[knikolla]

CCI-MOC/nerc-rates#42 implements storing outages in nerc-rates as YAML files. We should implement support for pulling outage information from there.

[jimmysway]

@knikolla I can also do this one but should we fill in the outages with the appropriate information first? Is there a list anywhere

[knikolla]

You can get started. There is a PR adding the Outages for October. This is all we need to get started since the monthly invoice that we need to process will only cover October.

[jimmysway]

@knikolla @QuanMPhm Should I complete get rid of the existing --exclude-time-ranges solution and the excluded intervals or should I keep it there for backwards compatibility

[knikolla]

@knikolla @QuanMPhm Should I complete get rid of the existing --exclude-time-ranges solution and the excluded intervals or should I keep it there for backwards compatibility

@jimmysway you can leave --exclude-time-ranges in there and have nerc-rates be used if there are no --exclude-time-ranges provided.