[enhancement] Allow copying templates

[Gitoffthelawn]

XPrivacy currently (v3.6.19) allows defining 5 unique restriction templates.

Request: Add the ability to copy all restrictions from one template to another.

To keep it as simple as possible, simply overwrite one template with another. For example, allow the user to copy the first template to the second template by simply overwriting the entire second template with all the restrictions from the first one.

This will allow creating templates that are based off of other templates.

[Cerberus-tm]

+1 This would be useful.