Improve group.state: any_on / all_on handling
Improve group.state: any_on / all_on handling

- Sanity check for proper groupId int > uint16
- Fix all_on when on == count but on == 0
- If any_on, all_on wasn't set yet, set it even if the value won't change.
  As side effect this will fire events shortly after startup. This can
  be useful for rules which otherwise would trigger only after values took
  a turnaround. It may be reverted though if it causes issues.
- Fix C++11 clang warnings

dresden-elektronik/deconz-rest-plugin,dresden-elektronik/deconz-rest-plugin,dresden-elektronik/deconz-rest-plugin,dresden-elektronik/deconz-rest-plugin,dresden-elektronik/deconz-rest-plugin