Duct: report pinning

[therealryan]

Duct will serve the reports generated by your test suites, but when you're iterating on something you'll be running them a lot and overwriting the previous reports. If you wanted to compare something between two instances of the same report you'd have to manually copy it somewhere and add it to duct again.

It'd be nice to make that easier - add a gui option to pin an indexed report. The report content could be copied to duct's directory and be indexed again. We'd need a bit more gui to manage pinned reports.