When committing tree imports, update plot if it is already present
Get importer commit working, and refactor it to return a partial
Remove irrelevant commented out HTML
Refactor auto-refreshing of importer list page

 - Change from pushing to a bus to merging streams for a few cases
 - Handle returning to the list page from the status page after commit
Merge pull request #1800 from maurizi/import-commit-updates

Importer commit updates