code: function renderTemplate(engine, filePath, content, context) {
      context = context || {};
  
      // Mutable objects to contains all blocks requiring post-processing
      var blocks = {};
  
      // Create nunjucks environment
      var env = engine.toNunjucks(blocks);
  
      // Replace shortcuts from plugin's blocks
      content = replaceShortcuts(engine.getBlocks(), filePath, content);
  
      return timing.measure(
          'template.render',
  
          Promise.nfcall(
              env.renderString.bind(env),
              content,
              context,
              {
                  path: filePath
              }
          )
          .then(function(content) {
              return TemplateOutput.create(content, blocks);
          })
      );
  }
docs: Render a template
  
  @param {TemplateEngine} engine
  @param {String} filePath: absolute path for the loader
  @param {String} content
  @param {Object} context (optional)
  @return {Promise<TemplateOutput>}