Improvement the way how permission schemes are associated with projects.

Currently, a project can has only one permission scheme associated. It must allow associate more than one permission by project.

Use the Permission Schemes Test Matrix exercises to check some scenarios, and add new ones: https://apps.xpand-it.com/confluence/pages/viewpage.action?pageId=203853411#PermissionSchemes%28WaitingforApproval%29-HowtoTestPermissionSchemeson5.0%28PermissionSchemesTestMatrix%29