Clarifying error message

This error will be triggered if either setting the group or the user is the problem.  Fixing the wording after being led astray tracking down issue that was group, not user, related.
Bug fix: get groupname of group rather than user
Add new feature, set file date to episode aired date. Fix, use alternative Trakt API field for episode air time. Improve the Preview Rename tip.

Add, new setting "Set File Date to Airdate" on the Media Management tab of the Settings page to toggle this feature for new, imported and auto updating media files.

Change, home page "Series Editor" - "Rename" button to "Update Files" and add "Set File Date To Air Date" action button to this modal to add capability of updating legacy media.

Add, non UTC functions given that Windows undesirably adds time to file times set when using UTC.

Fix, the Trakt API response show.air_time_utc contains erroneous data, this is replaced with show.air_time.
Merge branch 'AirDate' of https://github.com/JackDandy/NzbDrone into set-file-date
Set episode file modified date to local or utc air date
Merge pull request #58 from TectonicEd/patch-1

Clarifying error message
Merge pull request #59 from TectonicEd/patch-2

Bug fix: get groupname of group rather than user
Major logging overhaul
Removed Status from cleansed log messages
API Key in UI

New: view/reset API in General Settings
Fixed: API will reject unauthenticated requests
New: Set scanning interval for Drone Factory
Merge branch 'api-key' into develop
Added Mono version health check
Fixed test reference
DB will log Info and above now (temp fix)