Validate timestamp and nil fields in resources.lua

ElasticSearch has constrains of value type for existing fields.
So, we shouldn't send a string or invalid datetime information
into fields which have been already marked as datetime.
Validation and transformation invalid data is implemented in
this CR.

Change-Id: I8c91edc6e41d1a12fa792b2891d926e31d3171e6
1 file changed