Update documentation and remove commented code. Change from get type to getType().

src/canvasdrawer.js

@@ -85,7 +85,7 @@ class CanvasDrawer extends $.DrawerBase{
         return $.supportsCanvas;
     }
 
-    get type(){
+    getType(){
         return 'canvas';
     }
 

src/drawerbase.js

@@ -125,7 +125,7 @@ $.DrawerBase = class DrawerBase{
     /**
      * @property {String|undefined} type What type of drawer this is. Implementations should override this property.
      */
-    get type(){
+    getType(){
         return undefined;
     }
 

src/viewer.js

@@ -482,10 +482,8 @@ $.Viewer = function( options ) {
                 options:            this.drawerOptions[optsKey],
             });
             this.drawerOptions.constructor = Drawer;
-            // TO DO: add an event that indicates which drawer was instantiated?
             break;
         }
-        // TO DO: add an event that indicates that the selected drawer could not be created?
     }
     if(this.drawer === null){
         $.console.error('No drawer could be created!');