Add a catajson method to extract a list of strings as a set for use as tags.
Remove overloaded use of item::mode in preperation for turning it into a string field.
Remove unused flag parameter from item template constructors.
Remove obsolete item construction macros.
Move some library includes to the end of the list where they belong.
Convert item::item_flags to item::item_tags.
Also changing from a bit array to a set of strings.
Applying the same change to item::mode.
Clean up obsolete item flag enum and tag->enum mapping.
Merge PR #1033 - item tags as sets