Missing deps

Implements feature to be used in builder as discussed
@movitto I guess I still don't quite understand.  I guess what are the situations in which we have multiple instances of the same version against koji, git, yum?  For koji, I'm guessing, you get multiple versions of 1.0 if you keep the upstream source the same but build it multiple times with different release values.  Is that right?  What about git and yum?  

Then... why would 1.0 make sense for koji above, 3.0 for git, and 2.0 for yum?

I guess what I saying is I don't know that we have enough information to make that decision.  Should the consumer of these methods make that determination as to what is most relevant?