Add a way to allow requests by ip range

[josegonzalez]

We should read a label like:

'--label=openresty.allowed_ips=127.0.0.1 123.0.0.0/32'

If specified, we would add something like the following:

satisfy all;
allow 127.0.0.1;
allow 123.0.0.0/32;
deny all;

If we detect an openresty.basic-auth label with user:password combinations, we would instead use:

satisfy any;
allow 127.0.0.1;
allow 123.0.0.0/32;
deny all;

and add the basic auth after as appropriate.