perDocument port and back-button workaround

[andrewshumway]

port of perdoument changes from searchHub. Attempt fix for back-button

For comparison. Delete after review

[gsingers]

@andrewshumway Can you separate out the perDoc work from all of the other stuff? Also, you have things like ~ files checked in.

[andrewshumway]

I submitted this in response to some Q&A we had regarding back-button functionality. I had a work-around for problems but have doubts about the approach. You wanted to see the code and asked for a pull request. I never thought this would be merged up and so left the template code so as to give a complete picture.

If you think the back-button approach I'm using here has more merit than reworking all of this to use a $state or some sort of $route functionality where back-button behavior is baked in then I can re-submit with the template code removed. However, I've identified a couple of problems already with what's here in this pull-request.