* libs/common: refactor libs common 3
- move nil.go into types folder and make private
- move service & baseservice out of common into service pkg
ref #4147
Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>
* add changelog entry
* [libs/events] add more godoc comments
* [libs/events] refactor code
- improve var naming
- improve code structure
- do not use defers for unlocking mutexes (defer takes time)