Create new user page box display with title "Delegations (RC)"

It would be useful to add a new box on a single user's page view for RC delegations

The new box will fetch the user’s current RC delegations (querying RC delegations) which will allow finding to which accounts the user currently delegates rc, and the amount he delegates to each account.

The display will be somewhat similar to witness votes, but we need to also add the amount of delegated RC as a 3rd column.