Let the HTML filter encode all character entity references.

This is done by modifying the 'escapeCharacters' parameter on the filter's default configuration, and changing the encoding used to produce these files to ascii.
Make fedault output encoding be ASCII for the HTMLAdapter.

This is to force CERs (Character Entity References) to be present in the file, making it the safest option when displaying in a browser.
The file can still be converted to UTF-8 if desired using tools like 'encode' and the command line client's hooks.