Store user password in session

[WolfgangEibner]

After login the user password should be stored in the user's browser session for using it in the subsequent REST calls.

Django should use a memcached session db (https://docs.djangoproject.com/en/dev/topics/http/sessions/#using-cached-sessions) and additionally encrypt the user password.

Additionally clear the password/session manually at user logout.

[WolfgangEibner]

User password is already stored in session. Maybe memcached session db should be configured.

[fetzig]

• added outcommented snippet to setup memcached as default cache and session_engine
• pylibmc has been installed on the server

need a memcached url or socket to activate this.