Changeset 11438 with Emu 776

[osemu] Forbid parallel access to the key db even more
[powervu] Increase usuable EMM keys per group id to 32
Previously the EMM algorithm was using the first 16 EMM keys for each group id. If there were more EMM keys for a group, they were simply ignored. Now the capacity has been increased to 32 keys. Also did some minor optimizations and added comments to the code.
[powervu] Whitespace clean up
[osemu] Whitespace clean up