updated demo for message dates

MessagesDemo/DemoViewController.h

@@ -11,5 +11,6 @@
 @interface DemoViewController : JSMessagesViewController
 
 @property (strong, nonatomic) NSMutableArray *messages;
+@property (strong, nonatomic) NSMutableArray *dates;
 
-@end
+@end

MessagesDemo/DemoViewController.m

@@ -19,14 +19,24 @@
 - (void)viewDidLoad
 {
     [super viewDidLoad];
+    
     self.title = @"Messages";
     
+    self.dateLabelPolicy = JSMessagesViewDateLabelPolicyEveryThree;
+    
     self.messages = [[NSMutableArray alloc] initWithObjects:
                      @"Testing some messages here.",
                      @"This work is based on Sam Soffes' SSMessagesViewController.",
                      @"This is a complete re-write and refactoring.",
                      @"It's easy to implement. Sound effects and images included. Animations are smooth and messages can be of arbitrary size!",
                      nil];
+    
+    self.dates = [[NSMutableArray alloc] initWithObjects:
+                  [NSDate distantPast],
+                  [NSDate distantPast],
+                  [NSDate distantPast],
+                  [NSDate distantPast],
+                  nil];
 }
 
 #pragma mark - Table view data source
@@ -46,10 +56,17 @@
     return [self.messages objectAtIndex:indexPath.row];
 }
 
+- (NSDate *)dateForRowAtIndexPath:(NSIndexPath *)indexPath
+{
+    return [self.dates objectAtIndex:indexPath.row];
+}
+
 - (void)sendPressed:(UIButton *)sender withText:(NSString *)text
 {
     [self.messages addObject:text];
     
+    [self.dates addObject:[NSDate date]];
+    
     if((self.messages.count - 1) % 2)
         [JSMessageSoundEffect playMessageSentSound];
     else