Adds progress to find all references

Progress is added via the status bar.  This was done via making a unified API with the FSharp.ViewModule ProgressManager, so the same code can report to either (or both) locations.

In addition, improves rename to match, so it reports progress to status bar as well as dialog.

Addresses Issue #516

Also: Fixes dialog height for comment in #511

Could you change the formatting of DU to 

type StatusIcon =
     | General
     | Print
     | Save
     | Deploy
     | Synch
     | Build
     | Find

to be consistent with the rest of the code base?