Corrected inaccurate sentence.

If you have multiple shards, you will need to have a group of config servers for each cluster. --> If you have multiple sharded clusters, you will need to have a group of config servers for each cluster.

Signed-off-by: Sam Kleinman <samk@10gen.com>
Changes collection to namespace

Since you shard on the namespace - e.g. "mydb.users" - and not "users", this commit helps remove the ambiguity between namespace and collection for this page.

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