Make LUInstanceSetParams handle pnode parameter
Make LUInstanceSetParams handle pnode parameter

If pnode is set LUInstanceSetParams now sets the primary node
accordingly. Unless force is set, it is verified that the instance
is no longer running on the old node.

Signed-off-by: Klaus Aehlig <4ce51de36d9068cd7db2eec1151e0f3f95419008@google.com>
Reviewed-by: Guido Trotter <f62ca4d5358bdaeef0e50e57f9f7e231de63727e@google.com>

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