PullToRefreshView

It is:
 - a pull-to-refresh implementation
 - very easy to implement
 - doesn't suck
 - compatable with ARC and non-ARC
 - works from the top or bottom of the screen

To implement it:
 - add the five files (PullToRefreshView.{h,m}, ARCMacros.h, arrow.png and arrow@2x.png) to your project
 - add the Quartz framework to your project if you haven't done so yet
 - #import "PullToRefreshView.h"
 - add QuartzCore to your project
 - add an ivar: PullToRefreshView *pull; // or whatever you want to name it
 - in loadView or viewDidLoad, add this (and be sure to release in dealloc/viewDidUnload, etc):
    pull = [[PullToRefreshView alloc] initWithScrollView:<your scroll view here> atBottom:YES/NO];
    [pull setDelegate:self];
    [<your scroll view here> addSubview:pull];
 - in dealloc and viewDidUnload, add calls to:
   [pull containingViewDidUnload];
   to unwind the view hierarchy.
 - implement two delegate methods:
    // called when the user pulls-to-refresh
    - (void)pullToRefreshViewShouldRefresh:(PullToRefreshView *)view;
    // called when the date shown needs to be updated, optional
    - (NSDate *)pullToRefreshViewLastUpdated:(PullToRefreshView *)view;
 - call -finishedLoading on the PullToRefreshView when you finished loading (or got an error, etc)
 - that's it! no need to forward on UIScrollView delegate methods or anything silly like that.