688 feature complete roomcast implementation

[JoelWiebe]

Details

• Added isActive status for each activity phase
• Fixed display of play/stop button for each activity based on isActive value
• Created backend logic for fetching the current active phase
• Created basic RoomCasting UI
• Push and stop activities for appropriate room cast users
• Added embeddable CK Ideas Agent for SCORE authoring and room cast

TODO

• Test that web sockets still work for CK Workspace
• Test that projects still create properly and existing projects open properly
• Verify that resources push based on groups appropriately
• Verify that clicking stop removes the activities from all project members
• Verify that a user joining a currently running project will still receive the proper resources (even if room cast was not open when the activity began)
• Verify that students cannot open the CK Ideas Agent from the room cast, only teachers can open this tool

Closes #688