Update design doc for partitioned Ganeti
Update design doc for partitioned Ganeti

PVs don't need to be marked as unallocatable, as the code will ignore
partially used PVs. exclusive_storage made a node parameter.

Signed-off-by: Bernardo Dal Seno <dcdd79c5479cb9d1329ec01d126f02cb045aa103@google.com>
Reviewed-by: Iustin Pop <acf83a5274f31a43af6b914614365999469c1a31@google.com>

andir/ganeti,mbakke/ganeti,ganeti-github-testing/ganeti-test-1,leshchevds/ganeti,ganeti/ganeti,dimara/ganeti,apyrgio/ganeti,andir/ganeti,andir/ganeti,apyrgio/ganeti,leshchevds/ganeti,yiannist/ganeti,bitemyapp/ganeti,bitemyapp/ganeti,apyrgio/snf-ganeti,ganeti-github-testing/ganeti-test-1,ganeti/ganeti,grnet/snf-ganeti,grnet/snf-ganeti,onponomarev/ganeti,dimara/ganeti,yiannist/ganeti,mbakke/ganeti,yiannist/ganeti,leshchevds/ganeti,apyrgio/snf-ganeti,onponomarev/ganeti,mbakke/ganeti,ganeti/ganeti