Multi::API: Tighten input validation for integers

This fixes a vulnerability where one could remotely crash Multi by
sending a large integer in a filter. PostgreSQL will throw an error if
an integer is out of range for the selected data type, and Multi shuts
itself down on an SQL error.

(I've known about this vulnerability for quite a while, but it's good to
see how nobody has exploited it yet.)
Multi::API: Added 'get votelist'
Multi::API: Added 'get vnlist' and 'get wishlist'
Multi::API: Added 'set' command 'set votelist'
Multi::API: Added 'set vnlist'
Multi::API: Added 'set wishlist' command
d11: Minor doc improvements
Multi::API: Added 'tags' flag and member to 'get vn'
Added daily-generated JSON dump of the tag information

This isn't documented yet.
d11/d14: Added documentation for the tags dump