Use public api, move functions into public api

@forki I worked a bit on https://github.com/fsprojects/Paket/issues/341 - please offer guidance and I can continue if you like the direction. 

Thanks, 

Brody 

Need review on:

* Should these be public APIs?
* What should be done with bool flags?
Yes, I delayed cleanup on that while I checked with you for the overall direction of the PR. Fix welcome.