docs: public static String readDesignerVersion(ServletContext context) {
          String retStr = "";
          BufferedReader br = null;
          try {
              InputStream inputStream = context.getResourceAsStream("/META-INF/MANIFEST.MF");
              br = new BufferedReader(new InputStreamReader(inputStream,
                                                            "UTF-8"));
              String line;
              while ((line = br.readLine()) != null) {
                  if (line.startsWith(BUNDLE_VERSION)) {
                      retStr = line.substring(BUNDLE_VERSION.length() + 1);
                      retStr = retStr.trim();
                  }
              }
              inputStream.close();
          } catch (Exception e) {
              logger.error(e.getMessage(),
                           e);
          } finally {
              if (br != null) {
                  IOUtils.closeQuietly(br);
              }
          }
          return retStr;
      }