Fix nimsoft_logmon_watcher provider

The provider for the `nimsoft_logmon_watcher` type was not able to
create a new watcher rule because the method `root` of the provider
class is a class method, not an instance method.
Add new type nimsoft_logmon_exclude

The new type `nimsoft_logmon_exclude` can be used to create an exclude
rule for a specific logmon profile.
Merge branch 'logmon_exclude'

* logmon_exclude:
  Add new type nimsoft_logmon_exclude
  Fix nimsoft_logmon_watcher provider