I should be able to see help side-by-side with Querki

(User Story, To be Fixed , Priority: Medium, Test Status: No automated tests yet , Reported By Justin du Coeur, )
Documentation
Summary: Help should open in a side-panel, rather than a separate tab -- it would be much more usable.
To make this work, I probably need to finish refactoring out the global space field in DataAccess. Then we could show multiple pages in one client. (Right?)
The main challenge here will be enabling the system to cope with multiple Spaces at once, instead of having spaceId and userName hardcoded in Client. How do we pass that information from the Page into Client.doCall()? I discussed this in Gitter, and it seems like having Client as a singleton may be a mistake -- there should probably be one per Page instead. There should probably be a ClientBuilder singleton that the Page uses, and then the Page exposes the actual Client and things using it can take that as an implicit param.