WIP
Made API call. Currently broken due to token.

also, green checkmark now shows up to indicate that the api call
returned.
Tidied up add-listing

Currently a hard-coded token.
Makes API call to create sell, checks for response and alerts user as to
what is happening
Rewrote Settings Page. Added Logout button to menu

Logout does nothing.
Settings page currently has 10 departments that can be selected. Need to
modify in the future to load dept list programmatically. Will wait until
this branch is merged to continue work.
Merge remote-tracking branch 'origin/create_sell' into Search_Results