(breaking): rename button `on*` to just `*` events
(breaking): rename button `on*` to just `*` events

Hypercubed/ngx-ui,swimlane/ngx-ui,swimlane/ngx-ui,swimlane/ngx-ui,Hypercubed/ngx-ui,swimlane/ngx-ui,Hypercubed/ngx-ui,Hypercubed/ngx-ui