Implement percent operators for config files

[rminnich]

There are still one or two missing; consider this a draft until they are finished.

Also, fix one or two nits found by golint.

This change introduces no new findings by golint, go vet, and golangci-lint.

Signed-off-by: Ronald G. Minnich [email protected]

[kevinburke]

Hey, just following up here - you mentioned this is a draft, are there other changes that need to be made?

[rminnich]

oops, sorry, this should no longer be draft, how does it look to you. I missed your review :-(