initialize_kelpy() changes, StandardLocations
	-initialize_kelpy function now returns a Screen object and a StandardLocations object. (check the demos for example use).
	-New StandardLocations class to compute onscreen locations easily (replaces the Spots() class that was formerly located inside Miscellaneous)
	-Some stimuli images have been resized.
	-Demos have been adjusted to reflect these changes.
Merge!
Merge branch 'master' of https://github.com/piantado/kelpy

We needed to merge this, so we did.