Car Database Editor

I have a database that contains car makes, models etc. It has a tree structure. I need a dedicated editor that will allow my team to easily modify it. The changes have to be tracked and synchronized across open editors. The database has to be connected to the existing Inventory System; the changes should be visible in available options in the Inventory System dialogs. Requirements: * The editor should be a web based application. * The access to the editor should be restricted. There will be two levels of access: editor and viewer. The editor will be able to make changes and the viewer can only browse the database. * The access level will be defined in the Google Spreadsheet. The app will have to query the Google Spreadsheet to get the access level for a given email/user. * The editor has to allow add, edit, delete operations on a 4 level tree structure. The levels are: make, model, engine, engine code. * The application should allow a concurrent use. It means that the state of the database and changes should be synchronized across all open editor instances. * All changes have to be tracked. The editors should be able to view the history of changes and be able to restore the state of the database to a previous point in time. * The database has to be accessible from an Inventory System. The editor has to propagate changes to the Add, Edit, Review dialogs in the Inventory System. 2. Permissions spreadsheet I need a more fine grained access control for the Inventory System Spreadsheets. A new permission - Admin - should be added for the Inventory service. It would control who has access to directly editing Data sheets within inventory spreadsheets. A change in the permission should automatically update all the Google spreadsheets within Inventory Service.