Allow a content type only once (Only One) (7.x-1.13) - en to cy translation catalogue (4 entries)

en: Save configuration
cy: Cadw ffurfweddiad

en: Content
cy: Cynnwys

en: The configuration options have been saved.
cy: Mae dewisadau ffurfweddu wedi ei gadw.

en: Language neutral
cy: Iaith niwtral
