code: function visitContracts (contracts, cb) {
    for (var file in contracts) {
      for (var name in contracts[file]) {
        if (cb({ name: name, object: contracts[file][name], file: file })) return
      }
    }
  }
docs: call the given @arg cb (function) for all the contracts. Uses last compilation result
  stop visiting when cb return true
  @param {Function} cb    - callback
   @TODO has been copied from remix-ide repo ! should fix that soon !