Handler.dox:

- Small link fix
- Clean up the titles of the subsections a bit: these are reused in the looper documentation and they sort of clashed before.

Also, new documentation for Looper.dox!

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24304 a95241bf-73f2-0310-859d-f6bbb57e9c96

docs/user/app/Handler.dox

@@ -135,6 +135,10 @@
 	This method does not remove the handler from the looper to which this
 	handler is associated. You should do this yourself, using
 	BLooper::RemoveHandler().
+	
+	\warning This constructor does no type check whatsoever. Since you can pass
+		any BMessage, you should - if you are not sure about the exact type -
+		use the Instantiate() method, which does check the type.
 */
 
 
@@ -193,7 +197,7 @@
 
 
 /*!
-	\name Core Functionality
+	\name Core Handler Functionality
 */
 
 
@@ -240,8 +244,8 @@ ShowImageApp::MessageReceived(BMessage *message)
 	will reply with a \c B_MESSAGE_NOT_UNDERSTOOD constant. 
 	
 	\attention If you want to keep or manipulate the \a message, have a look
-		at the \link BLooper::DetachMessage() DetachMessage() \endlink method
-		to get ownership of the message.
+		at the \link BLooper::DetachCurrentMessage() DetachCurrentMessage() \endlink
+		method to get ownership of the message.
 	
 	\param message The message that needs to be handled.
 */