Purpose: look up the authenticated web user's details.
URL: https://www.commcarehq.org/api/v0.5/identity/
Sample Response:
{ "id": "672bdfc8-3629-10e0-9e24-005057aa7fe5", "username": "demo@dimagi.com", "first_name": "Demo", "last_name": "User", "email": "demo@dimagi.com" }