Add graphql support for portfolio page

[RusseII]

amount column in portfolio? how to get this. from gql, do i have to aggregate the bids and collect their full size for each bond?

Hmm, that's a good question. The portfolio page should show the porter bonds that the currently connected user has, and the amount should be the quantity for each bond. I don't believe this data is currently easily fetch-able via graphql but it should be. Use a dummy value for now, I'll create an issue to make this data available via graphql

Originally posted by @RusseII in #69 (comment)