Note to remove Bootstrap::lib when debugging
Allow use of %c with Git::Tag (RT#99990)

  Add Dist::Zilla::Role::Git::StringFormatter and make Commit & Tag use it.
Use %c in Git::Tag tests
v2.027

 - unify string formatting code into Dist::Zilla::Role::Git::StringFormatter
   This allows you to use %c (the changelog entry) with Git::Tag.
   (christopher madsen, suggested by doug bell - rt#99990)