LDEV-61 Fixing tool sessions - all users were getting separate tool sessions. Changed name of "group" to "sessionGroup" so that the HQL wouldn't throw warnings about group being a reserved word.
added the property groupingTypeId, which previously wasnt there. when retrieving Grouping objects, the groupingTypeId was null regardless of what value was stored on database. Works okay now.
DB Changes: lams_tool: columns learning_library_id and default_tool_content_id made nullable (C Perfect's request). lams_user: column user_organisation_id removed (checked with F Yang)