Party registration workflow

This MR contains the implementation for #17

The workflow logic is the following:

1. A user is created manually on Keycloak
2. An OSL Admin logs in and creates an individual with the same username
3. The OSL user with role TESTBED_PROVIDER logs in OSL and lands in page individual_update/myuser and enters the geographic location info of the site that manages
4. (Optional) If the user wishes can navigate again to the page via edit my profile and can update its information