Distributed queries response metadata

[luzrain]

Problem:
If we use distributed queries to write, as example

DROP TABLE IF EXISTS test_table ON CLUSTER test_cluster

the answer will be contains metadata in table format which can't be parsed in ClickHouseDB\Statement::init() and as a result throws "Can`t find meta" exception.
This pr fixed it by adding JSON format for queries started from CREATE, DROP or ALTER.
This does not affect on non-distributed queries as the response to these queries contains nothing for those type of queries.

[isublimity]

Thx!