#comment lowercased all device ids
- added tools directory
- created migration script for z-push-2.0 to 2.1 (lowering all device ids in the states)
- changed IStateMachine interface to get and set state versions
- defined two state versions (for 2.0 and 2.1 M1)
- implemented state versions getter and setter into FileStateMachine
- ZPush::GetStateMachine() checks for correct state versions and throws HTTPReturnCodeException otherwise
- ZPush::GetLatestStateVersion() indicates the latest version of the states implemented
- changed Request to always lowercase the device ID
- changed z-push-admin to always lowercase the entered device ID

git-svn-id: https://z-push.org/svn/z-push/trunk@1613 b7dd7b3b-3a3c-0410-9da9-bee62a6cc5b5