Add information about basic module structure and file extensions

Author: paultcochrane

lib/Language/modules.pod

@@ -19,6 +19,20 @@ to a type of package declared with the C<module> keyword (see example
 below) but here we mostly mean "module" as a set of source
 files in a namespace.
 
+=head2 Basic Structure
+
+Module distributions in Perl 6 have the same stucture as any distribution in
+the Perl family of languages:  there is a main project directory containing
+a C<README> and C<LICENSE> file, a C<lib> directory for modules, a C<t>
+directory for tests, and possibly a C<bin> directory for executable programs
+and scripts.
+
+Module files generally use the standard C<.pm> extension, and scripts or
+executables use C<.pl>.  However, if you wish to highlight that the file is
+written in Perl 6 you can use the C<.pm6> extension for modules, and the
+C<.p6> extension for scripts.  Test files still use the normal C<.t>
+extension.
+
 =head2 Loading and Basic Importing
 
 Loading a module makes the packages declared within available in the
@@ -286,3 +300,5 @@ C<use Vortex::TotalPerspective>, and your Perl 6 implementation will
 know where to look for the module file(s).
 
 =end pod
+
+# vim: expandtab shiftwidth=4 ft=perl6