We were using v1.0.0 of Cobra as newer versions added spf13/viper as dependency,
which came with many indirect dependencies. Cobra v1.6.0 and up no longer depend
on viper, so we can now safely upgrade to the latest version.
full diff: https://github.com/spf13/cobra/compare/v1.0.0...v1.6.1
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
