Imported overlord solution

Joe/Sophia,
I spent this morning re-doing my level_up fork and branches. I believe it is correct now. Each task now has its own branch containing nothing other than changes pertinent to the task itself.

I'm resubmitting a code-review pull-request for overlord.

Zamir
Shouldn't these be default parameters, not empty strings? Also, possibly incidentally, couldn't the bomb just accept only integers and you could let the app take care of casting strings?