change, by querying the config instead of StatSummarizer to
   determine if a stat is graphed.
  - Don't append to a string in a loop
  - parseConfig() return a Set instead of List to avoid O(n**2) behavior
    when deteriming config changes

   - Remove unused imports

            rendering code (ticket #890)

            (tickets #715 and #743)
 * SystemVersion: Centralize more methods here

    and determine Java version on Android

    NPEs in the finalizer, probably was the root cause of
    what we blamed on Jetty

      - Disable zh translation in graphs on windows due to font issues
      - Fix NPE at startup
      - Graph tweaks

    - Disable graphs on JVMs that crash

    - Refactor handling of required stats
    - Shorten description of required stats
    - Improve save messages on configstats.jsp
    - Change bw.sendBps and bw.receiveBps stats to bytes, not Kbytes
    - Expires directive for graphs

- Fix HTML errors
- Refresh improvements
- Fix Rate.equals() bug
- More cleanups

- Restart line in graphs
- Restore zh fonts in graphs

      - Tag text in graphs
      - Move SummaryRenderer to its own file

      for efficiency (thanks Arsene for the suggestion)