Feature/hover card

- [x] Ready for merge

Preview:

![http://d.pr/i/Uf6L+](http://d.pr/i/Uf6L+)

Currently might be a bit too intrusive, but need to try some more user types and states.

Workings for different states: http://jsbin.com/UliDUmeS/3/edit?css,output

Tasks:

- [x] works in incognito
- [x] works viewing another owner
- [x] works as owner
- [ ] changes when privacy state changes?
- [x] add streaming count (perhaps can be returned in save xhr payload instead of persistent stream?)