docs: function goVersions () {
    return new Promise((resolve, reject) => {
      https.get(gtagOpts, (res) => {
        let json = ''
        res.on('error', reject)
        res.on('data', (data) => (json += data.toString()))
        res.on('end', () => {
          let tags = []
          try {
            json = JSON.parse(json)
          } catch (ex) {
            return reject(ex)
          }
          for (let entry of json) {
            let vStr = entry.ref
            if (vStr.indexOf('refs/tags/go') !== 0) continue
            vStr = vStr.substr(12)
            let svNums = vStr.split('.').map((n) => +n)
            if (svNums[0] !== undefined && Number.isNaN(svNums[0])) continue
            if (svNums[1] !== undefined && Number.isNaN(svNums[1])) continue
            if (svNums[2] !== undefined && Number.isNaN(svNums[2])) continue
            let major = svNums[0] || 0
            let minor = svNums[1] || 0
            let patch = svNums[2] || 0
            tags.push({vStr, major, minor, patch})
          }
          let rels = tags.sort((a, b) => {
            let aScore = (a.major * 10000) + (a.minor * 1000) + a.patch
            let bScore = (b.major * 10000) + (b.minor * 1000) + b.patch
            return bScore - aScore
          }).map((tag) => tag.vStr)
          return resolve(rels)
        })
      }).on('error', reject)
    })
  }