Changing ownership of a collection

[envycontent]

There is a nice admin interface to change ownership of a collection from one person to another.

The drop down list for this gives a list of all the usernames of people within the system - it would be great if this list were in alphabetical order as there are so many users now that it is hard to find the right one (tip is to hover over the person in the user list, find their number, which gives you a rough idea of where they might be in the drop down list...)

This is relatively low priority as changing collection ownership doesn't happen very often (we've just had a run on them recently).

[envycontent]

see #493