Set common standards for Ktlint projects

[paul-dingemans]

Like the Commonhaus Foundation we do not want to impose a lot of standards on the Ktlint projects managed by this organization. We should detemine which standards are the bare minimum for a project that is managed.

Suggested topics to discuss:

• Use maven coordinates org.ktlint, io.ktlint for top level
• Use same code of conduct, contributing, and security guideline