What are the features of Deal Room in Vtiger CRM? What are the benefits of Deal Room? What are the functions of Deal Room? How do I send the Deal Room Invitation to Contacts? What is the Deal Progression Bar in the Deal Room? What is the Questions section in the Deal Room? What is the Files section in the Deal Room? What is the Timeline section in the Deal Room? How do I add Contributors in a Deal Room? How does a Contact add Contributors (members) to the Deal Room? How does a Contact schedule a meeting in the Deal Room? How does a Contact upload files in the Deal Room? How does a Contact log into the Deal Room? How does a Contact log out of the Deal Room? What are the various sections of the Deal Room? How do I keep track of time spent on a Deal stage?