SetDefaultHandler calls L.SetHandler, so init doesn't need to call it a
second time.
Rework to move assembly into a separate type and methods. Clean up the
code and comment it.
Remove unused functions. Consolidate utility methods from other files
into here. Comment code.
Add tracking of uploads so we know when an upload has finished. Rework
the upload code to clean it up and make more robust. Comment code, and
add in logging.