Improve Staff Details view

[profcturner]

The Staff Details view could now do with some potential enhancements, including, potentially:

• it would be better if one could delete activities directly from here, now.
• it would be better if one could edit activities directly from here, now.
• it would be better if one could create a custom activity for this staff member from here, now.
• it would be possible to create a small coloured square against each workload category (as in the load chart view)
• there is now, potentially, more information in the Staff model that might viewed here (job title, school and faculty)

There are a few things to consider here... for instance, if deleting an activity from here, the redirect should come back. May need to implement more push / pop redirects.