Save meta values when checkout form submits
Confirms that the most recent meta values are saved when the checkout form is submitted.  The checkout values are restored into customer meta.  THis should be a very inexpensive safeguard against race conditions as the WOrdPress meta infrastructure checks values as they are stored to be sure they are changed.  Unchanged value store attempts noop very quickly
Merge pull request #1320 from JeffPyeBrook/pr-1315-confirm-meta-values-on-checkout

Save meta values when checkout form submits