Move general Identity Service settings to global settings

Current Situation

• The Identiy Serivces page offers to "Manage General Settings" such as the idle session timeout, initial password and minimum password length.

Desired Behavior

• General Identity Service settings are moved to the global Settings page.
  • Section: identity_service
  • Settings:
    • idle_session_timeout
    • initial_password
    • minimum_password_length