Merge pull request #3 from doodles526/working

added nil datastore tags to XMLName
feat(omaha): add disablebackoff field to action

another extension added by the the chromeos update engine
fix(omaha): create section for update_engine extensions

add this comment section just so it is a littlemore clear what is going
on.
feat(omaha): add more update_engine extensions
Merge pull request #4 from philips/update-engine-extensions

Update engine extensions
terminated XMLName from appearing in json
when we need json encoding(putting AppRequestLogs into bigquery)
we don't want the XMLName tag adding on needless data