ANSI type coercion rule for date time operations

Currently the type coercion rule `DateTimeOperations` doesn't match the design of the ANSI type coercion system:
1. For date_add/date_sub, if the input is timestamp type, Spark should not convert it into date type since date type is narrower than timestamp.
2. For date_add/date_sub/time_add, string value can be implicit cast to date/timestamp only when it is literal.

Thus, we need to have a new rule for the date time operations in ANSI type coercion system.