Some Javascript refactoring.

* Moved all initialisation stuff to init_plemp().
 * No longer set and user BaseUrl but use document.baseURI instead.
 * Added the function key_handler() for handling key presses.
 * Added functionality to dismiss the add/upload dialog when pressing Escape.

plemp.rb

@@ -126,7 +126,7 @@ module Plemp::Views
                  :type => "text/javascript"
         end
         script :type => "text/javascript" do
-          "BaseUrl = \"#{URL()}\";\nsetup_pu()";
+          "init_plemp();"
         end 
       end
       body do

public/dragreg.js

@@ -1,3 +1,9 @@
+// Main function to initialise plemp
+function init_plemp(base_url) {
+  setup_pu();
+  document.onkeyup=key_handler;
+}
+
 // Creates a Draggable for each div with the given ID.
 function setup_draggable(id) {
   drag = new Draggable(id, { scroll: window });
@@ -20,21 +26,34 @@ DragRegObserver.prototype = {
   onEnd: function (eventName, draggable, event) {
     if (Draggables.activeDraggable.element == this.element) {
       elem = draggable.element;
-      new Ajax.Request(BaseUrl + 'savepos/' + elem.id + 
+      new Ajax.Request(document.baseURI + 'savepos/' + elem.id + 
                        '/' + elem.style.top + '/' + elem.style.left);
     }
   }
 }
 
-//// Helper functions
+// Global function to handle key presses.
+function key_handler(e) {
+  var key_code = e.keyCode;
 
-function show_add_dialog() {
-  $('text').clear();
-  $('add_dialog').appear({duration: 0.5});
+  switch(key_code) {
+    case 27:
+      hide_add_dialog();
+      break;
+  }
 }
 
+//// Helper functions
+
+// Shows the upload/add dialog.
+function show_add_dialog() {
+  $('text').clear();
+  $('add_dialog').appear({duration: 0.25});
+}
+
+// Hides and clears the upload/add dialog.
 function hide_add_dialog() {
-  $('add_dialog').fade({duration: 0.5});
+  $('add_dialog').fade({duration: 0.25});
   $('add_form').reset();
 }
 
@@ -61,7 +80,7 @@ function move_draggable_if_needed(id, left, top) {
 var pu = null;
 function setup_pu() {
   if (!pu) {
-    pu = new Ajax.PeriodicalUpdater('', BaseUrl + "current/", {
+    pu = new Ajax.PeriodicalUpdater('', document.baseURI + "current/", {
            method: 'get',
            frequency: 5,
            evalJSON: 'force',