endpoint for micro-credit global data dashboard

[vibern0]

See designs https://www.figma.com/file/hdfvUzjBN7yA9hlB4eG3Fe/Website?node-id=10512%3A117655&t=FwF5Zgmg5yFCoSV1-1

Some data will be coming from TheGraph, some other from the backend, but that data we won't have on this first phase, such as "total applicants" and "in review"

Dependent on impactMarket/subgraph-micro-credit#1

[vibern0]

Base data is indexed

{
  microCredit(id: "0") {
    borrowed {
      asset
      amount
    }
    debt {
      asset
      amount
    }
  }
}

https://thegraph.com/hosted-service/subgraph/impactmarket/alfajores-microcredit