Fix: Searching for propers/repacks at nzbs.org.

If no results are found with the usual search URL, an alternate is tried.
Fixes issues with settings and newznab providers.
Fix for failed releases not properly converting scene numbered to indexer numbering plus small typo fix.
Fixed issue for season searches using episode only mode but fallback to season only mode, was small typo correction
Merge pull request #573 from JackDandy/FixSearchNzbsOrg

Fix: Searching for propers/repacks at nzbs.org.
Fixed find propers.
Added ability to force a find propers search.
Fxi for failed downloads