Add option to query by array of values

[nikajukic]

Example:

class ContainerType < Enumerations::Base
  value :db_20, name: 'DB 20', type: 'DB'
  value :pp_20, name, 'PP 20', type: 'PP'
  value :ot_40, name: 'OT 40', type: 'OT'
end

ContainerType.where(type: ['DB', 'PP'])