move off deprecated azer/Debug dependency for debugging solution

[mroth]

Some options:

• https://github.com/azer/logger
• https://github.com/rs/zerolog
• https://github.com/sirupsen/logrus (thx @nerney)
• https://github.com/uber-go/zap

Logging will need to be documented in the README as well, since it's essential for someone who would be using this package in production.

[nerney]

another good option: https://github.com/sirupsen/logrus (it's what docker uses)

[mroth]

With the changes in 5338305, a logging solution is no longer required, as it can be left up to the end implementation, as is probably more appropriate. Debug is now only used for actual DEBUGGING in development.

That said, it may be worth pulling Debug out of the codebase since it's deprecated. Changing the name of this Issue according.