put use lib into the index

doc/Language/modules.pod6

@@ -337,16 +337,21 @@ Then use the tag you like and pick the symbol by its name.
 
 =head2 Finding Modules
 
-A user may have a collection of modules not found in the normal
-ecosystem but needed regularly.  Instead of using the C<lib> pragma
-one can use the C<PERL6LIB> environment variable to point to module
-locations.  For example:
+X<use lib>
+A user may have a collection of modules not found in the normal ecosystem,
+maintained by a module or package manager, but needed regularly.  Instead of
+using the C<use lib> pragma one can use the C<PERL6LIB> environment variable to
+point to module locations.  For example:
 
     export PERL6LIB=/path/to/my-modules,/path/to/more/modules
 
 Note that the comma (',') is used as the directory separator (instead
 of the colon (':') as with Perl 5 for C<PERL5LIB> or C<PERLLIB>).
 
+The include path will be searched recursively for any modules when Rakudo is
+started. Directories that start with a dot are ignored and symlinks are
+followed.
+
 =head1 Distributing Modules
 
 If you've written a Perl 6 module and would like to share it with the