parsing of date ranges in queries no longer consults the
index mapping. it was deteremined that this wasn't very useful
and led to overly complicated query syntax/behavior.
instead, applications get set the datetime parser used for
date range queries with the top-level config QueryDateTimeParser
also, we now support querying date ranges in the query string,
the syntax is:
field:>"date"
>,>=,<,<= operators are supported
the date must be surrounded by quotes
and must parse in the configured date format
