Exposing module services in a Page Engine based application

Using the following API for both site and page definitions, it is now possible to expose a module controllers methods as services which you can then have access to by using the new <code>getServices()</code> method from the <code>aria.pageEngine.PageEngine</code> class:

```
         module1 : {
             ...
             services : {                
                 'MyServiceMethod1' : 'exposedMethod1',
                 'MyServiceMethod2' : 'exposedMethod2'
             }
         },
         module2 : {
             ...
             services : {
                 'MyServiceMethod3' : 'exposedMethod3',
                 'MyServiceMethod4' : 'exposedMethod4'                 
             }
         }

```