Get ENS domain and icon of orchestrators

[stronk-dev]

We can do this separately in each src/OrchAddressViewer.js
Wait for ENS and/or Ceramic support to be implemented first, since 3box is deprecated

[stronk-dev]

Waiting for livepeer/explorer#55

[stronk-dev]

We should keep an eye on ensdomains/ens-metadata-service#50 in order to display avatars for ENS domains with emoji's

[stronk-dev]

Plan of action:

Add /getENS endpoint to API:
  for now only return the ENS domain name of a given eth address
  dont forget to add a timestamp to the data
  cache it as UNSET if there is no associated ENS data

Since there is a tiny set of Orchestrators, have the loadingscreen preload all cached ENS data
  It should throw away any results which are more than X minutes old, maybe once a day?

Edit src/components/eventButtonAddress.js:
  Initially just render the original address like now
  If there is no (recent) associated ENS data, request ENS info of this O
  If we have one in the redux store, set the ENS domain name as the name
    Still display the first X chars of the actual address
    Display an ENS icon as default avatar
      Make it link to app.ens info page of the website
      Also try to get an avatar from https://metadata.ens.domains/mainnet/avatar/<ENS URL>/meta
        Maybe try a separate resolver (like 1inch is doing) while above function is borked for emoticon urls

Expand txt search to also filter by name, rather than only the O address

[stronk-dev]

done