Add role prefix to role specifig variable to avoid conflicts when
using multiples role on the same machine on the same play.

Role to configure nextcloud with LDAP User backend.

First test passed.

New modules:

- occ:
  set coniguration values using `php occ` nextcloud command-line tool.

- remove the handling of which template to use
- do not access parent role
- update riot-web nginx configuration
- update icinga role to use new nginx templating
- update synapse nginx configuration
- update matrix role to use new nginx templates
- update dokuwiki to use new nginx template
- extend nginx template in dokuwiki
- update login role to new nginx templates
- add protocol for default option
- add extra block to nginx template
- update riote-web version
- fix template extension for riot web nginx definition
- update login template for nginx endpoint