changed transforms import

The transforms is in the util folder now, and isn't in the examples part
anymore, so it should be imported from util
removed swap_buffers call (redundant)

Removing swap_buffers call, since it's automatically called now.  Also
removing the call to use glut, since this is unlikely to work on most
windows machines (and qt works fine for me).
added tailed arrow marker
Merge branch 'master' of https://github.com/vispy/vispy
Merge pull request #60 from joe311/master

Tailed arrow marker