Also, recursively perform VACUUM and ANALYZE on partitions when the
command is applied to a partitioned table.  In passing, some related
documentation updates.

Amit Langote, reviewed by Michael Paquier, Ashutosh Bapat, and by me.

Discussion: http://postgr.es/m/47288cf1-f72c-dfc2-5ff0-4af962ae5c1b@lab.ntt.co.jp