tests: added some tests for some of the app dialogs

still haven't found a way to close modal dialogs, so those aren't being
tested yet
Merge branch 'master' of github.com:peircej/psychopy
BF: fixed bug when using ElementArrayStim with numpy 1.7.1

caused by the new need to force things into contiguous order when doing
reshapes/concatenates. Symptom was that most of the elements came up
with sf=0 (ie very noticeable error)
FF: new bug with scaling of images when size=None

The code to track requestedSize was set /after/ size had been given a value
so always had a value even when the user didn't request one.