Team Foundation Service: Process template changes

Updated process templates for Agile (version 6.1), CMMI (version 6.1), and Scrum (version 2.1) in Team Foundation Service. For Agile, the User Story state model was updated to allow transitions between any states. For Scrum, the same was done for Product Backlog Item and Bug. CMMI's ResolvedBy, ResolvedDate, ActivatedBy, and ActivatedDate fields were corrected for specific transitions. The primary motivation for these changes is the industry trend towards less restrictive process flows, highlighted by the limitations observed with Kanban boards where moving back to a previous state was not possible.