Merge pull request #2 from cythoplazma/master

Pull request.
Merge pull request #3 from cythoplazma/master

Pull request.
Transition osx application build scripts tu use git.
Fixed a ValueError in Orange/data/preprocess/scaling.py

Due to the seed for numpy.random being to large (numpy 1.9.x)
Use git to update orange in windows installer build script.
Cleanup windows installers build directory structure.
Fixed obsolete url.
Added special 'orange-sf' search path prefix.
Follow redirects in ImageLoader.

(this is equivalent to
biolab/orange3/e0d3990d5338993c65e609b130e7867fb4510b8e)
Explicitly remove items from layout before repositioning them.

Fixes a warning from Qt.
Merge branch 'master' of github.com:biolab/orange