Make our registry hives Win2k3-friendly

There are two problems currently present in ReactOS, that makes our registry hives not Win2k3-friendly:

• the Max(Value)[Name|Data]Length members of the HBIN structures are not initialized in the mkhive-built hives;
• Win2k3 demands the presence of CM_KEY_SECURITY hive blocks, otherwise it refuses to mount the hive saying it is corrupted (technically it isn't since the security blocks are not fundamentally a part of the registry, but they are required by Windows). Currently they are not set at all by ReactOS, and worse, we fake their existence by creating suitable security information on the fly instead of retrieving it from the hive.