if min and max are the same term
and the term is in dictionary
and both in and max are set to exclusive
then we would panic attempting to access element -1 of a slice.
now, after trimming the slice, we recheck that the length is > 0
The term range query is not often used in full-text queries, but
can be useful when filtering on keyword indexed text terms in
the index.
The JSON syntax to do a TermRange query is the same as for
NumericRange, but the min/max values must be string and not
float64.
