Use request path to identify current project

Note:
  In this document I use project to refer to the also known name tenant.

The current implementation to switch between projects use a session stored in a cookie. This can create a strange behavior when we try to use more than two windows/tabs open with different projects in a same browser because the session is shared. (mismatch between projects).

I suggest to extract the project Id from the session to pass it to the request path and so avoiding this behavior.

About the implementation:
  + To follow the current path pattern, we can add a new rule to handle the project id by that way:
        https://example.org/project/{project_id}/

  + Switching between projects means using different tokens. The current implementation of sessions may need to keep track of tuples (project Id, token).