message: Update NEWS for 2.1
diff: +Version 2.1
  +-----------
  +
  +- Added import and export of translation memory as TMX files.
  +- Added ability to delete bad translations from the TM.
  +- TM now has limited support for plural forms (only nplurals<=2).
  +- Improved handling plural form rules. CLDR is now used as the data source and
  + expressions are checked for equivalence before warning about unusual forms.
  +
  +
  Version 2.0.9
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