Make 'modify ssh setup' queryable
Make 'modify ssh setup' queryable

This enables the config to be queried for the configuration
parameter 'modify ssh setup'. This will later be used in
gnt-node add.

Signed-off-by: Helga Velroyen <2d0126b1ec6f9ec5cbec4a7012aa14faeaef10f5@google.com>
Reviewed-by: Klaus Aehlig <4ce51de36d9068cd7db2eec1151e0f3f95419008@google.com>

ganeti/ganeti,ganeti/ganeti,andir/ganeti,yiannist/ganeti,mbakke/ganeti,andir/ganeti,ganeti/ganeti,leshchevds/ganeti,leshchevds/ganeti,onponomarev/ganeti,mbakke/ganeti,andir/ganeti,yiannist/ganeti,yiannist/ganeti,mbakke/ganeti,onponomarev/ganeti,leshchevds/ganeti