Team and Member code need a redesign

[cpeel]

The team and member code in stats/ needs a redesign and to follow sensible coding practices like not using global variables. The teams code should be rewritten using a class that handles all DB accesses and image upload manipulation.

An example bug is the teams code supports previewing edits but does not correctly persist the avatar and icons across previews. It also does DB manipulation in the image upload function which is unexpected from a design perspective.