Adds suspend event mapped to application lifecycle

On Android WillSuspend and WillResume maps to focus and DidSuspend and
DidResume maps to onPause and onResume.

On OSX WillSuspend and DidSuspend maps to resign key, WillResume and
DidResumg maps to make key.

examples/common/entry/entry.cpp

@@ -464,7 +464,10 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 				case Event::Window:
 					break;
 
-				default:
+                case Event::Suspend:
+                    break;
+
+                    default:
 					break;
 				}
 			}