(QENG-1087) beaker - failure in XML output

- caused by improperly stripping unsupported unicode characters from xml
  output
- add inclusion of 'jcode' for ruby 1.8 (included with Ruby and adds
  lots of useful Unicode-oriented features to String and Regexp)
- tested on 1.9 and 1.8 and correctly replaced invalid unicode with
  escaped hex value
Might be worthwhile to use << here and below as it modifies the existing string object rather than creating a new one.