Fix what I noticed during the current sweep through the docs.

Signed-off-by:Master Yoda <jim_parry@bcit.ca>

public/robots.txt

@@ -0,0 +1,2 @@
+User-agent: *
+Disallow: 

user_guide_src/source/concepts/structure.rst

@@ -22,6 +22,7 @@ structure that works well for many applications. The following folders make up t
 		/Controllers    Controllers determine the program flow
 		/Helpers        Helpers store collections of standalone functions
 		/Language       Multiple language support reads the language strings from here
+		/Libraries      Useful classes that don't fit in another category
 		/Models         Models work with the database to represent the business entities.
 		/Views          Views make up the HTML that is displayed to the client.
 

user_guide_src/source/contributing/internals.rst

@@ -25,7 +25,7 @@ provide a way for dependencies to override that::
 Type hinting
 ============
 
-PHP7 provides the ability to `type hint <http://php.net/manual/en/functions.arguments.php#functions.arguments.type-declaration?`_
+PHP7 provides the ability to `type hint <http://php.net/manual/en/functions.arguments.php#functions.arguments.type-declaration>`_
 method parameters and return types. Use it where possible. Return type hinting is not always practical, but do try to
 make it work.
 
@@ -61,8 +61,8 @@ CamelCase class and file names. The should be in their own directory that matche
 directory.
 
 The the Router as an example. The Router lives in the ``CodeIgniter\Router`` namespace. It has two classes,
-**RouteCollection** and **Router**, which are in the files, **system/Route/RouteCollection.php** and
-**system/Route/Router.php** respectively.
+**RouteCollection** and **Router**, which are in the files, **system/Router/RouteCollection.php** and
+**system/Router/Router.php** respectively. 
 
 Interfaces
 ----------
@@ -71,6 +71,10 @@ Most base classes should have an interface defined for them. At the very least t
 and passed in other classes as a dependency without breaking the type-hinting. The interface names should match
 the name of the class with "Interface" appended to it, like ``RouteCollectionInterface``.
 
+The Router package mentioned above includes the 
+**CodeIgniter\Router\RouterCollectionInterface** and **CodeIgniter\Router\RouterInterface**
+interfaces to provide the abstractions for the two classes in the package.
+
 Handlers
 --------
 

user_guide_src/source/general/environments.rst

@@ -12,7 +12,7 @@ The ENVIRONMENT Constant
 ========================
 
 By default, CodeIgniter comes with the environment constant set to use
-the value provided in ``$_SERVER['CI_ENV']``, otherwise defaults to
+the value provided in ``$_SERVER['CI_ENV']``, otherwise defaulting to
 'development'. At the top of index.php, you will see::
 
 	define('ENVIRONMENT', isset($_SERVER['CI_ENV']) ? $_SERVER['CI_ENV'] : 'development');