Make it possible to track previous values on Term details every after update

[RoiJS]

Overview

Today, the user can be able to update the term details assigned to the contract. Any updates on the term details will only take effect on the future statement of accounts but not on the existing ones anymore. This means that the current setup of the term details will no longer match with the existing statement of accounts and this could lead to confusions just in case the system failed to generate a correct statement of account details. So, to make the investigation much easier, I decided to introduce something on the internally so the investigation will be much easier, and this is to introduce the concept of term versioning. If there are any changes applied on the term details assigned to the contract, the system will not perform update on the term but instead it will create a new copy and just keep the old data. Technically, we will need to introduced new table that will keep track on the previous versions of terms assigned to the contract.

TODO

• Introduce new table called TermVersions.
• Introduce new DataRepository for the term version
• Update the logic inside the Update function on ContractControler
• Make sure to create a new version of the term if there is modifications.
• Test and verify

[RoiJS]

It is now possible to keep the previous version of terms every after updates. Information are stored on table TermVersions.
Moving this issue to close now.