* Add new connection checks and tests
* Enable concurrent output and previous connections on blocks
* and remove assumption from unplug().
* Make changes compatible with new module system
* Fix issue do to Connection class change.
. and change some var's to const's now that that appears to be ok ;-)
* Fix more code that assumes only one of output and previous connections
* Change function name as per PR comment
* Fix lint errors
* Fix clang format issues