Refactor how config and certificates are being read about waffle

[wrik0]

@cebilon123 I'm picking this up. I'm assuming you'd like the options for a .env file use as well as a load from os environment as well. I'd like to add validation for certs, the PEM keys during the initial load itself rather than the invocation during proxy.Server.Start(). LMK if you approve.

[cebilon123]

Go on. This needs a love, great idea with the validation and env reading. I was thinking about scaling it up, and the kubernates would be a way to go, but this needs to be researched more (so the env would be needed in the future. You can write some handy abstractions because we would use it in the collector as well)