Prober support more exporters

[bck01215]

What is missing?
The ability to add specs to prober to fit exporters beyond blackbox-exporter

Why do we need it?
Support a variety of exporters including custom exporter
Environment

Anything else we need to know?:

Currently the prober spec is designed to fit around blackbox exporter. Other exporters like the snmp and ntp exporter as well as some custom ones require different paramaters on the probe to be submitted The prober spec does not appear to allow for custom paramaters

[aureliano911112]

hsp msp