Enable continuing a run

[gonzalezem]

Orna is great. It does take a while to run though on bigger projects (no criticism here). Then you run on a server, the specified time does not always allow for the entire script to run. My issue is that when you rerun it, it starts all the way back to the beginning which can be frustrating when you where close to the end (we're talking multiple days of run). I tried to hack the program, but I couldn't find an easy way to do this. Would it take forever to add a --continue flag to process it automatically. I really like your work though, I think it's great. Cheers!