Allow staff to edit sort order from the client
Currently, when an instructor adds materials from the web form, they are given a default sort order of 0*. When we add materials from the client side, they are given no sort order at all and there is no way to add them. This ultimately creates two lists of materials, the ones with no sort order and then the ones with a sort order of zero. There is no way of fixing this, short of deleting the materials added from the client and uploading them again from the web form.
*When custom sort is enabled, the sort order will be higher.