Jeffrey Yu

@samad-yar-khan Thanks for the insights! Like my comment above, I think having token & URL stored in a singleton solves the issue of fetching themevery time. Whenever the user updates...

Implemented the singleton approach and applied to all migrated methods in this PR and in #144. Behavior same as before: 

The singleton gets api host from environment and generates access token when initialized. We'll need to update these when user update settings / login / logout in another PR.