[CAL-3514] Drag & drop for re-ordering event types

[lantai5]

It takes too long to click every time over and over and over and over to move an event up when I have 10+ events.

_CAL-3514

[sanjay-sol]

Hey @lantai5,
I'm thinking of transform that into a feature allowing users to drag events to different locations.

cal-21.mp4

[sanjay-sol]

Hey @ciaranha , can I start working on this??