Log Message:
Updated to version 3.20.

Pkgsrc changes:
  - Introduced USE_LANGUAGES.

Relevant changes since version 3.19_01:
=======================================

    [THINGS THAT MAY BREAK YOUR CODE]
    * The store_declarations() method has been restored, but defaults
      to true instead of false.

    [THINGS THAT MAY BREAK YOUR CODE]
    * The store_declarations() method has been removed.
    * Non-closing HTML tags like <IMG> are now rendered as <IMG />.
    * All values in tags are now double-quoted.  Previously, all-numeric
      values weren't quoted.