PowerSTIG needs to generate config js and cfg files in order to be compliant with Firefox STIG

[japatton]

Describe the bug
PowerSTIG does not create the required js and cfg files for Firefox STIGs. Unless the user places those files ahead of time, the STIG will throw errors.

To Reproduce

1. Create and apply Firefox MOF.

Expected behavior
When applying a configuration with the Firefox STIG, PowerSTIG should determine if the files are present and if not, create the files and then populate them with the correct information.