Sort anyway if masterlist update takes too long or fails

[sibir-ine]

Requested by Psymon & IllusiveMan on Discord.

They are requesting that if Update masterlist before sorting is enabled & the masterlist update procedure hangs or fails, LOOT notifies the user & proceeds to sorting anyway. In the case that it hangs, this would require setting a max time after which the masterlist update procedure is canceled.

At present, when the masterlist update procedure fails (e.g., when there's no internet connection) before sorting, LOOT appears to crash. This doesn't occur when just the Update Masterlist button is pressed, it just returns an error. This might be a separate bug.

[Ortham]

• I'd need to change up the tasks code to support more complicated chaining, as masterlist update is prelude then masterlist, and if prelude fails we'd want to skip masterlist and go to sort, and if masterlist fails we'd want to go to sort. That's fine, it's just not trivial.
• Yeah, there's no default timeout, I can add one easily enough. Qt's default (if you set a timeout without specifying a value) is 30 seconds, which seems reasonable.
• I see why LOOT is crashing, the handler doesn't account for the possibility that the process might have completely failed, it always expects at least one task to finish. That's easy enough to fix.

[Ortham]

The crash is fixed in 67c7fd5 and the network timeouts have been added in bc5a440.