* Consolidate certificate supplier module
Both the proxy and the proxy needs certificate suppliers. The PR
consolidates the module that providings those bindings to a shared
module and switched the proxy to use that module. The prober currently
uses P12 file to store its certificates. I am debating keeping that
supplier ro converting them to PEM files for simplicity.
* Rename mode enum values to be more descriptive
* Update annotation names to be more descriptive
Client SSL handler already performs the necessary validation. Only tests are
added.
Server SSL handler does not currently check for the validity period of
the client certificate as the insecure trust manager is used. This PR
added the check but does not actually terminate the connection yet. It
will log the expired certificates so that we can contact the registrars
to update them.
Once we are certain that all certificates are updated, we can turn off
dryrun mode.
We should also consider checking if the certificate has too long a
validity period as it defeats the purpose of using regularly updated
certificates to deprecate insecure cipher suites.
