change plural to singular in balancer tutorial
Minor: Removing repeated sentence

Signed-off-by: Sam Kleinman <samk@10gen.com>
Update db.copyDatabase.txt

Including an example. There are at least a few cases on the web where folks ( i hit this too) neglected to put quotes around the database name. Hopefully with a live example that will no longer happen

Signed-off-by: Sam Kleinman <samk@10gen.com>