Delegation history and list for DReps

### Why

So Dreps can see and understand who's delegating to them and how much Voting Power is involved

### What

Delegators need to know several things about their delegees:

- Who's delegated to them
- how much voting power has been delegated and by whom
- What is the date of the delegation
- If an 'un-delegation' event happens

### How

This would work as a table in the delegator's detail card. It should be available to the public.