Ingress validate currently validates config from a file. This PR adds a
new --json/-j flag to provide the ingress/config data as a plaintext
command line argument.
* `max-fetch-size` can now be set up in the config YAML
* we no longer pass that to filter commands that filter by name
* flag changed to signed int since altsrc does not support UInt flags
* we now look up each non UUID (to convert it to a UUID) when needed, separately
Tunnel delete is successful even if we don't find the credentials
file in the user's filesystem. We no longer "error" indicating this
is a problem. This fix also enables chaining of the delete command
by removing a pre-mature return if the credentials file is not found.