message: Chore: Update CHANGELOG.md prior to release.
diff: +## X.Y.Z (INSERT_DATE_HERE)
  +
  +#### Minor Changes
  +- [Support MultiMode Lexer definitions in Parser Constructor.](https://github.com/SAP/chevrotain/issues/395)
  +
  +
  +
  ## 0.27.2 (3-31-2017)
  #### Minor Changes
  