Cocoa Memory Management Fixups

A number of memory management errors fixed, no doubt there
are more lurking in there.

* CocoaInitializer now sets up an application wide NSAutoreleasePool
* Kickr now init/releases an NSAutoreleasePool for its thread
* Local autorelease pools in constructors etc have been removed
* Searchbox and Button no longer release in the constructor

The icon corruption seems to be improved (I think it is a memory
management issue) but has not been totally removed.