- add support for .commit-msg.d

When enabled run scripts within .commit-msg.d/agnostic
and .commit-msg.d/<GOOS>

- better gitlab ci handling

- use go modules

- add support for GitLab CI linter

- fix a bug where body lines where multiplied by the number of ignore expressions

- add support for co-authored-by

rename binary

code quality improvements

merge: branch 'release/0.6.0'

merge release branch

remove v1 config handling

add external tools
fix optimistic verison handling

version two of config

name for rule
severity for rule