Enable Managing Editor access to Editorial options on Applications

* Added Editor and Editor Group facets to "Applications" section of admin area
* Created logical separation between admin vew on suggestions and the code which handles suggestions/suggestion form (which will allow us to then have other routes into that code from the editor area
* Added "Editorial" section to suggestion form template
* Ported similar functionality for handling editorial details from the journal handler
* normalised the usage of the suggestion form with editorial features with the public-facing Apply form, and fixed a bunch of minor issues in doing that