Provide the ability to limit a Portfolio Manager rights to only the Portfolio they manage

We want to be able to limit a Portfolio manager to only have manager access to "their" portfolio. (ex: creating projects on in their portfolio)

With the current functionality, if I provide someone portfolio manager rights, they get that same access to all portfolios. This causes pain when we have an inexperienced portfolio manager or one that may not follow the rules. Ex: If PersonA is the Porftolio Manager for ABC Portfolio -- they should not have the same rights in XYZ portfolio.