Make Reported Event objects stringify rich data

ORIGINAL

An option is needed in the ToDataConverter so that warnings for stringification of rich data is suppressed. This is needed because there is legitimate use cases where stringification is required.

UPDATE

The legitimate use case was in Event objects in reports. There, rich-data cannot be allowed because nothing downstream from the report is prepared to handle rich data. The specification for reports even say that all values in Events (before/after) are supposed to be strings, but that is a lie since it is any JSON data type (but not any additional "rich data" encoding.