Add documentation as requested by pdk validate

3 jobs for master
Status Job ID Name Coverage
  Syntax
canceled #119
syntax lint metadata_lint check:symlinks check:git_ignore check:dot_underscore check:test_file rubocop-Ruby 2.5.3-Puppet ~> 6

 
  Unit
canceled #121
parallel_spec-Ruby 2.4.5-Puppet ~> 5

canceled #120
parallel_spec-Ruby 2.5.3-Puppet ~> 6