Added a simple help popup for chat

mod/chat/README.txt

@@ -6,9 +6,15 @@ Version 0.2  (for Moodle 1.1)
 This module is still very new and very incomplete compared
 to what it will be one day.
 
-It's based in part on ARSC but I ended up rewriting so much 
-of it there's hardly a line of code in use that has not
-been changed, so perhaps it's better to say *inspired* by ARSC.
+It's based in part on:
+
+    ARSC: A Really Simple Chat
+    by Manuel Kiessling
+    http://manuel.kiessling.net/projects/software/arsc/
+
+but I ended up rewriting so much of it there's hardly a line 
+of code in use that has not been changed, so perhaps it's 
+better to say *inspired* by ARSC.
 
 Things to do yet:
 

mod/chat/gui_header_js/chatinput.php

@@ -22,6 +22,9 @@ require_login($chat->course);
 <html>
 <head>
 <title>Message Input</title>
+
+<?php include("$CFG->javascript"); ?>
+
 <script language="Javascript">
 <!--
 scroll_active = true;
@@ -43,6 +46,7 @@ function empty_field_and_submit() {
 <form action="../insert.php" method="GET" target="empty" name="f" 
       OnSubmit="return empty_field_and_submit()">
 &gt;&gt;<input type="text" name="chat_message" size="60" value="<?php echo $chat_pretext; ?>">
+<?php helpbutton("chatting", get_string("helpchatting", "chat"), "chat", true, false); ?>
 </form>
 
 <form action="../insert.php" method="GET" target="empty" name="fdummy"