Unnecessary import in phylotree. Fix #60
Merge branch 'optimal_scale' into stable
Merge branch 'optimal_scale' into stable
Merge branch 'optimal_scale' into stable
removes the creation of a test.svg file every time a tree is visualized.
fixes #86 missing source and target attributes in NexmlTree export
Merge branch 'stable' of github.com:jhcepas/ete into stable
merge with latest fixes in stable branch