code: async function srcToDocs (dir) {
    const location = path.join(srcPath, dir)
    const srcFiles = await getFiles(location, (item) => item.path.endsWith('.js') && !item.path.endsWith('index.js'))
    const filesContents = await readFiles(srcFiles)
    const filesComments = srcFiles.map((location, index) => {
      const fnName = path.basename(location).replace(/\.js$/, '')
      const matter = getMatter(fnName, dir)
      const doc = matter.concat(extractComments(filesContents[index])).concat(getRuleImport(fnName))
      return { comments: doc.join('\n'), location }
    })
    await writeDocs(docsDir, filesComments)
  }
docs: Converts all source files inside a directory to `.adoc`
  files inside docs directory
  
  @method srcToDocs
  
  @param  {String}  dir
  
  @return {void}