simultanous use checking and cleanups

* implement requested simultaneous use checking
* update documentation to reflect new feature
* cleanup misc switch formatting
* cleanup and move token logic to fetch functions
* remove unused bits from json_missing.h
* change extra verbose logging to level 3 only
* misc json_object_put cleanup and wrapping
Merge pull request #837 from leprechau/feature/check_simul

Implement and document requested simultaneous use checking feature.