add new NSBrowser test

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/tests/examples/trunk@37156 72102866-910b-0410-8b05-ffd578937521
NSSlider-test/NSSlider-test.m: Add a circular slider


git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/tests/examples/trunk@37187 72102866-910b-0410-8b05-ffd578937521