LDEV-61 Fixing tool sessions - all users were getting separate tool sessions.Modified library activities to use GROUPING_SUPPORT_OPTIONAL as the grouping support type.
various changes including* change the values of contentId and sessionId* remove most of the remove/recreate code when saving existing contents* updated file upload methods
Modified the "leaveToolSession" and related code to allow the tool to pass the userid (which it gets from UserDTO in the shared session) rather than pass User (which the tool doesn't have).
Modified the "leaveToolSession" and related code to allow the tool to pass the userid (which it gets from UserDTO in the shared session) rather than pass User (which the tool doesn't have).