Remove old instance attributes
Remove old instance attributes

Reviewed-by: ultrotter

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