This commit add handling for dropping of chunks and hypertables
in the presence of associated compressed objects. If the uncompressed
chunk/hypertable is dropped than drop the associated compressed object
using DROP_RESTRICT unless cascading is explicitly enabled.
Also add a compressed_chunk_id index on compressed tables for
figuring out whether a chunk is compressed or not.
Change a bunch of APIs to use DropBehavior instead of a cascade bool
to be more explicit.
Also test the drop chunks policy.
0db50e7ffc