index: Don't drop query parameters when redirecting to dashboard
iframe: Load JavaScript even when 'isIframe' is true
Use lowercase username and user groups for loading user permissions and restrictions
Resources: Support type 'ini' yet only in the resources.ini

Configuring the resource type 'ini' via the web interface is not yet possible.
lib: Add UserGroupBackend as base class and factory for user group backends
lib: Replace Membership with IniUserGroupBackend
lib: Add DbUserGroupBackend
DbConnection::__construct(): Set prefix if configured
Auth: Load user groups using the new user group backends
schema/mysql: Add group and group_membership tables
Update `icingaweb2_dev' profile's file 'config.ini'

refs #6842
icingaweb2_dev: provide Package[php-ldap]

refs #6842
schema/mysql: Add user and user_preference tables
Set php.ini's date.timezone = "UTC"

refs #6842
icingaweb2_dev: iptables: descend index of insertion

refs #6842
Merge branch 'master' into feature/deduplicate-puppet-code-6842