3.0 feature request - queuing multiple folders for compression (#82)

[anijatsu]

Hi,
This is similar to #82, but different since my personal workaround of running multiple instances at the same time is no longer possible - the beta now checks whether there isn't an already running instance of the program.
Because of that, whether I happen to gather a larger collection, or happen onto a slower HDD, I can't easily leave the computer overnight to parse through multiple games/folders at a time.
Would it be possible to add in a queue for folders to be processed as new functionality?
If there's any prompts needing user attention, like with submitting compression rate results, they could be predefined based on a setting in program's preferences, or remain as up for review when the user next views the program's status.

Initially eg. to avoid too many UI changes, it'd also be sufficient to be able to call the program from the command line, with it returning a success code after it's done processing the files. That way an external batch script could be written to handle multiple folders per run.