Refactor Pagure configuration
    
    - reconfigure to use Redix over a Unix socket
    - switch Redis configuration to pillar
    - delete nginx TLS configuration (production uses HTTP from the
      reverse proxy - internal TLS is still a TODO and can then be
      implemented in the pillar)
    - add common .jinja suffix and file header to templates
    - make state idempotent
    
    Signed-off-by: Georg Pfuetzenreuter <mail@georg-pfuetzenreuter.net>