code: function calculateVersion(officialRelease, callback) {
      var version = require('./package.json').version;
  
      if (officialRelease) {
          callback(version);
      } else {
          git.short(function (str) {
              callback(version + '+' + str);
          });
      }
  }
docs: Returns the version string in package.json, plus a semver build metadata if this is not an official release