code: function enumType (type, stateDefinitions, contractName) {
    var match = type.match(/enum (.*)/)
    var enumDef = getEnum(match[1], stateDefinitions, contractName)
    if (enumDef === null) {
      console.log('unable to retrieve decode info of ' + type)
      return null
    }
    return new EnumType(enumDef)
  }
docs: Enum decode the given @arg type
  
  @param {String} type - type given by the AST (e.g enum enumDef)
  @param {Object} stateDefinitions - all state definitions given by the AST (including struct and enum type declaration) for all contracts
  @param {String} contractName - contract the @args typeName belongs to
  @return {Object} returns decoded info about the current type: { storageBytes, typeName, enum}