…t_units to master

* commit 'c9a874227d62cd8ec63faa5e91d7aef7b209657e':
  Updated built files
  Added note to the change log about the fixed issue
  Fixed typo
  Updated per review, and added a check for a forgotten fromVal parameter in convertToBaseUnits
  Set the version to 5.0.0
  Corrected https://github.com/lhncbc/ucum-lhc/issues/45; changed convertToBaseUnits to return a status flag so that a warning message can be returned without meaning the conversion failed