exchanging gdt.core.heasarc.FtpFinder for gdt.core.heasarc.BaseFinder which now provides HTTPS file transfer by default with the option to select FTP if needed
re-naming TriggerFtp/ContinuousFtp to TriggerFinder/ContinousFinder
providing a backwards compatible implementation of TriggerFtp/ContinuousFtp by inheriting from TriggerFinder/ContinousFinder with protocol='FTP'
This pull request updates the gdt-fermi finder API to match the new BaseFinder class being added to gdt-core via PR https://github.com/USRA-STI/gdt-core/pull/57.
The changes include:
Docs and unit tests are updated.