Adding support to the BuddyPress Activity Meta commands:
$ wp bp activity meta
usage: wp bp activity meta add <id> <key> [<value>] [--format=<format>]
or: wp bp activity meta delete <id> [<key>] [<value>] [--all]
or: wp bp activity meta get <id> <key> [--format=<format>]
or: wp bp activity meta list <id> [--keys=<keys>] [--fields=<fields>] [--format=<format>] [--orderby=<fields>] [--order=<order>]
or: wp bp activity meta patch <action> <id> <key> <key-path>... [<value>] [--format=<format>]
or: wp bp activity meta pluck <id> <key> <key-path>... [--format=<format>]
or: wp bp activity meta update <id> <key> [<value>] [--format=<format>]
Adding support to the BuddyPress Activity Meta commands:
fixes #85