Add final configuration step

... for pointing teuthology at paddles.

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
Add missing setup step
Add note about using a real server for production
Add /queued/ API

Returns a list of runs that have any queued jobs

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
Use a much faster query for /runs/queued/

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>