title: How to write custom sort logic on sort column event in ng2-smart-table
body: <p>I'm looking to hook-up sort events performed on ng2-smart-table. Followed <a href="https://akveo.github.io/ng2-smart-table/#/documentation" rel="nofollow noreferrer">https://akveo.github.io/ng2-smart-table/#/documentation</a>, I see bunch of events that are exposed like rowSelect, mouseover  etc but I don't see sort events published/emitted by the library. I'm thinking of changing Ng2SmartTableComponent and emit an event when (sort) is called internally. May I know if anyone did it already or is there a hack I can rely upon.</p>