Function arcSafeRelease

extlibs/catch/include/catch/catch.hpp:1492–1494

#if !CATCH_ARC_ENABLED
inline void arcSafeRelease( NSObject* obj ) {
    [obj release];
}
inline id performOptionalSelector( id obj, SEL sel ) {
    if( [obj respondsToSelector: sel] )
        return [obj performSelector: sel];