A contract may be discharged in the following ways:
1. Performance according to its terms.
5. Rescission or renunciation by parol agreement.
7. Cancellation and surrender.
To these may be added two defences which generally are held merely to bar the remedy on the contract,
12. Statutes of Limitation.
A right of action upon a contract may be discharged in any of these ways except the second and the eleventh.