copy-edit and clean up of module001-ch009-vm-placement

copy-edit and clean up of document
added the for formality
capitalized Nova-scheduler
changed only and supports to make sense
removed , and ‘too” added , and that
changed define to defined
removed So, added the, changed to weighed

Change-Id: I47380b6cd0a811b4c9af0643fc55784f1f929942
Merge "copy-edit and clean up of module001-ch009-vm-placement"