disable date detection mapping by default

Currently, ES is configured with the default behavior whereby any strings that pass date detection are mapped to a datetime field. However, this can cause a problem is a dataset is not homogeneous. For example, a collection consisting of date from numerous providers may contain a field that has a value in numerous different datetime formats. If the first Item indexed uses a format the ES can parse to a datetime, the mapping is datetime then. However, some may have unparseable datetimes, which will then cause them to fail.

The fix for this is to set "date_detection: false" in the code where we currently set numeric_detection false.

Inspect the code where numeric_detection is currently set to false. Add the corresponding date_detection setting there, then verify that fields containing mixed or unparseable datetime formats are not automatically mapped as datetime fields.