Updating Template Inheritance docs

Author: EvanLovely

README.md

@@ -11,7 +11,7 @@ The Twig PatternEngine comes pre-installed with the [Pattern Lab Standard Editio
 Pattern Lab PHP uses [Composer](https://getcomposer.org/) to manage project dependencies with Pattern Lab Editions. To add the Twig PatternEngine to the dependencies list for your Edition you can type the following in the command line at the base of your project:
 
     composer require pattern-lab/patternengine-twig
-
+o
 See Packagist for [information on the latest release](https://packagist.org/packages/pattern-lab/patternengine-twig).
 
 ## Overview
@@ -76,12 +76,12 @@ Would be used like this in a pattern:
 
 ### Template inheritance
 
-The requirements for using template inheritance with Pattern Lab:
+How to use [Template Inheritance](http://twig.sensiolabs.org/doc/templates.html#template-inheritance) with Pattern Lab:
 
-* Files can optionally go in `source/_layouts` in order to hide them from the list of patterns.
-* Files must have the extension `.twig`
-* Files can be extended either by using Pattern Lab's normal shorthand syntax (e.g, `{% extends 'templates-extended-layout'%}`), 
-  or, if they are in the `source/_layouts` directory, by using just the filename as reference (e.g., `{% extends 'extended-layout'%}`).
+* Files must have the extension `.twig`.
+* Files can be extended either by using Pattern Lab's normal shorthand syntax (e.g, `{% extends 'templates-extended-layout'%}`).
+* Files can optionally go in `source/_layouts` in order to hide them from the list of patterns and then you can just use the filename as reference (e.g., `{% extends 'extended-layout'%}`).
+* Files that are in the same directory can also just use the file name without the shorthand syntax (however, it must include the extension). So if `file1.twig` and `file2.twig` were in same directory, you could place this code in `file2.twig`: `{% extends 'file1.twig' %}`. 
 
 An example of a simple layout called `base.twig` in `source/_layouts`:
 
@@ -125,6 +125,8 @@ Would be used like this in a pattern:
 {% endblock %}
 ```
 
+All uses of `extends` above also work with `includes`, `embed` and most likely many other Twig Tags. Let us know if you run into interesting or unexpected use cases!
+
 ## Extending Twig Further
 
 Twig comes with a number of ways to extend the underlying template parser. You can you can add [extra tags](http://twig.sensiolabs.org/doc/advanced.html#tags), [filters](http://twig.sensiolabs.org/doc/advanced.html#filters), [tests](http://twig.sensiolabs.org/doc/advanced.html#tests), and [functions](http://twig.sensiolabs.org/doc/advanced.html#functions). The Twig PatternEngine tries to simplify these extensions by allowing you to create files in specific folders and then auto-load the extensions for you. Learn more about: