def read_publishable(dir, magic_dir, matcher)
      read_content(dir, magic_dir, matcher)
        .tap { |docs| docs.each(&:read) }
        .select { |doc| processable?(doc) }
    end
def read_publishable(dir, magic_dir, matcher)
      read_content(dir, magic_dir, matcher)
        .tap { |docs| docs.each(&:read) }
        .select { |doc| processable?(doc) }
    end
Read all the files in <source>/<dir>/<magic_dir> and create a new
 Document object with each one insofar as it matches the regexp matcher.

 dir - The String relative path of the directory to read.

 Returns nothing.