This shifts notification routing into the matcher-system. Every
notification has associated metadata (key-value fields, severity -
to be extended) that can be match with match directives in
notification matchers. Right now, there are 2 matching directives,
match-field and match-severity. The first one allows one to do a
regex match/exact match on a metadata field, the other one allows one
to match one or more severites.
Every matcher also allows 'target' directives, these decide which
target(s) will be notified if a matcher matches a notification.
Since routing now happens in matchers, the API for sending is
simplified, since we do not need to specify a target any more.
The API routes for filters and groups have been removed completely.
The parser for the configuration file will still accept filter/group
entries, but will delete them once the config is saved again. This is
needed to allow a smooth transition from the old system to the new
system, since the old system was already available on pvetest.
Signed-off-by: Lukas Wagner <l.wagner@proxmox.com>
