New to 1.14, Mojang stores .mca files which don't contain chunks in the
poi folder.
Note: we explicitly filter *out* the poi folder, instead of filtering
*to* the regions folder, since old versions of minecraft had regions
directly in the world folder (instead of a regions subfolder).
This change fixes the block count report, and also makes
naturalize act more like a "//replace dirt grass" where
we only attempt block changes if the block is not already
what we're looking for.
They now additionally take a direction in which the simulated item usage
should be facing.
Also allow the item parser to parse "hand" and "offhand" as items, to
allow platforms with NBT item support return items with NBT (since
parsing is a slightly more complex task).
If multiple namespaces are present, suggestions will first suggest a
namespace, then once a namespace is selected, keys within that namespace.
Starting an argument with ":" will instead search across all namespaces
for matching keys.
Later registered parsers will always come before the default, ensuring
that the default parser is used when no other parser can match the input,
and that errors may be thrown by it to signify the end of the line.
All patterns now have suggestions, including recursive patterns.
Suggestions will suggest blocks and block states.
All masks now have suggestions, though mask intersections are not
yet supported due to issues with quotes strings.
EntityRemover and ItemFactory now also have completions, as well
as all RegistryConverters (though I am unsure how many are actually
used).
Also use paper's AsyncTabComplete event, if available.
