[io grant] Amend IO::Path.resolve: :completely

To include the bit that the last path fragment does not have to exist.

Rakudo correction: rakudo/rakudo@51e462925a
Tests: Raku/roast@a716962791

Author: zoffixznet

doc/Type/IO/Path.pod6

@@ -343,10 +343,11 @@ for each directory in the path, and any symlinks found are followed.
     # bar is a symlink pointing to "/baz"
     my $io = "foo/./bar/..".IO.resolve;      # now "/" (the parent of "/baz")
 
-If C<$completely>, which defaults to C<False>, is set to a true value, the
+If C<:$completely>, which defaults to C<False>, is set to a true value, the
 method will L«C<fail>|/routine/fail» if it cannot completely resolve the path,
 otherwise, it will resolve as much as possible, and will merely perform
-L«C<cleanup>|/routine/cleanup» of the rest of the path.
+L«C<cleanup>|/routine/cleanup» of the rest of the path. The last part of the
+path does B<NOT> have to exist to C<:$completely> resolve the path.
 
 NOTE: Currently (April 2017) this method doesn't work correctly on all
 platforms, e.g. Windows, since it assumes POSIX semantics.