Updates test to check for template filling

And also updates a bit the README.md to reflect the use of templates. Refs #35 but shouldn't be closed unless it's documented actually on the code.

README.md

@@ -16,6 +16,10 @@ This module is in the [Perl 6 ecosystem](https://modules.perl6.org), so you inst
   simply disregard the test and install with `--force` if that
   particular feature is of no use to you.
 
+**Note**: Perl6 2018.11 introduced handling of Definition blocks,
+`Defn`. Please upgrade if you are using that feature in the
+documentation.
+
 ## SYNOPSIS
 
 From the command line:
@@ -55,6 +59,11 @@ say Pod::To::HTML.render($pod,
     lang => "document language (defaults to 'en')",
 	default-title => 'No =title was found so we use this');
 
+# If you want to use a specific template 
+say pod2html $=pod[0], :templates("lib/templates");
+# main.mustache should be in that directory
+
+
 ```
 
 ## DESCRIPTION

t/120-templates.t

@@ -1,10 +1,12 @@
-use Test;
+use Test; # -*- mode: perl6 -*- 
 use Test::Output;
 use Pod::To::HTML;
-plan 3;
+plan 4;
 my $r;
 
 =begin pod
+=TITLE The usual suspects
+
 The seven suspects are:
 
 =item  Happy
@@ -32,3 +34,4 @@ ok $r ~~ ms[[
 
 $r = pod2html $=pod[0], :templates("t/templates");
 ok $r ~~ ms[[  '<meta description="This is a new template"/>' ]], 'Gets text from new template';
+ok $r ~~ ms[[ "<h1 class='title'>The usual suspects</h1>" ]], 'Fills template correctly';