This builder is the one used to build the convenient result_set (not
on fast path). The builder was assuming that the whole set of columns
was always queried, which resulted in buffer underflow exceptions
during parsing of the results if this was not the case. Let's also
handle queries which have narrower column sets.
Add a query::result_set class that contains per-row cells that can be
accessed by column name. Partition keys, clustering keys, and static
values are duplicated for every row for convenience.
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
