samvermette/SVPullToRefresh — pull request #13 by chapados (2012-05-10 00:05:46+00:00)
Title: Ensure that pullToRefreshView stops observing scrollView properties.

Since the SVPullToRefreshView holds a weak reference to the scrollView,
it is possible for the scrollView to be nil by the time dealloc is called.
This situation leaks Key-Value Observers, triggering a runtime warning,
and leading to a potential crash.

These changes attempt to ensure that scrollView observers are added & removed
whenever the pullToRefresh view changes, and also during init/dealloc.