Project template relationship - allow removal

[#1]

Description - Allow project template relationships to be removed

Why is this feature important to you - The first project template is not always relevant. Sometimes projects are drastically modified. Sometimes a different template is attached later. 

How would you like the feature to work - In the edit interface and in the copy interface, allow for removal of the template relationship.

Current Behaviour - The first project template to be attached is there forever. Even when you make a copy of the project.

[#2]

This is a great idea.  I'd like it to update and even a way to show ALL templates that were used on the project like it shows all custom forms used. 

We'd like to report on how many projects use what templates so we can revise planned vs actual better and maybe retired templates not used.  It's impossible if the project template only shows the one template on there if we always start with a planning template. 

[#3]

We would also like to see ALL templates. We have several small templates that can be added to projects as needed - an additional round of revisions, translation needed when the original request did not include translation, minor updates after a project was completed, etc.