v0.0.31

• Break change word source removed from custom sources, enabled for markdown
  by default.
• Break change ignore sortText when input.length > 3.
• Break change show prompt for install coc-json when not found.
• Fix document content synchronize could be wrong.
• Fix filetype not converted on completion.
• Fix complete item possible not resolved.
• Improve document highlight, no highlight when cursor moved.
• Improve completion score, use fuzzaldrin-plus replace fuzzaldrin.