Clean up admin screen

[lucastbelem]

We'll detail the requirements a bit later, but I just want to capture that this is work we need to do. Things like:

• Double menu bar
• Wonky or unclear UI in certain screens
• UI uniformity for different screen sizes
• Extra, unnecessary empty screens
• Other things

[GeorgeBellTMH]

• All the items in the menu can be moved into a dropdown under admin...this is a relatively easy change and will simplify a lot...