Added CMS_CORE_MODULE which is the mandatory module for ROC CMS.

Added CMS_USER.profile_name .
Improved module managements with install vs enable.
  - enabled/disabled status can also be stored in database.
Install procedure do not install all available modules anymore.

examples/demo/site/themes/bootstrap/assets/css/style.css

@@ -47,6 +47,9 @@ ul.horizontal li {
   padding: 5px;
   font-style: italic;
 }
+#content .preview {
+  border: solid 1px red;
+}
 
 .sidebar {
   padding: 5px;

examples/demo/site/themes/bootstrap/assets/scss/style.scss

@@ -51,6 +51,9 @@ ul.horizontal {
 		padding: 5px;
 		font-style: italic;
 	}
+	.preview {
+		border: solid 1px red;
+	}
 }
 .sidebar {
 	padding: 5px;