Add Chinese Backend

Added

• Chinese thesaurus query support based on [[https://github.com/shijiebei2009/Algorithms/blob/master/src/main/resources/cilin.txt][cilin.txt]]
• backend forward/backward switching functionality (only available in normal
  mode Candidate Choosing Interface)
• =openoffice_en= backend, using OpenOffice's thesaurus extension as thesaurus
  source.

Fixed

• Bugs in miscounting utf-8 character length when replacing existing phrase with
  user chosen one.
• Bugs in source checking logic of =mthesaur_txt= routine when variable
  =&thesaurus= is searched

Removed

• word_list cache saving results found in previous query sessions