* Experiments with common equivocation trait
* Improved equivocation trait
* Fix grandpa equivocation implementation
* Remove some cruft
* Remove some more cruft
* More generic naming
* Simplification of offences manipilation
* More refactory
* Some prograss with the encapsulation of offence report system
* Finally unit type works as a universal null report system
* Align substrate node code
* Further simplification
* Fix test utils
* Remove not required associated type
* Fix benches
* Rollback to prev field name
* Box big params
* Fix typo
* Remove new tag computation
* Remove default implementations
* Better docs
* Return 'Result' instead of bool
* Change offence report system return types
* Some renaming and documentation
* Improve documentation
* More abstract offence report system
* Rename 'consume_evidence' to 'process_evidence'
* Further docs refinements
* Doc for dummy offence report
* Fix rustdoc
* Fix after master merge
* Apply code review suggestions
* Improve docs