Fully-qualified all imports in __init__.py.

This is slightly uglier than the existing `from .blah import X` but I
suspect it will fix #28. I have no way to test this but it passes
`nosetests` on 2.6 (I'll let TravisCI tell us about 3.x).

Minor tweak - made setup.py executable since I am in the habit of
typing `./setup.py develop`.
Merge pull request #30 from eigenhombre/fully-qualify-imports

Fully-qualified all imports in __init__.py.
version bump to 0.2.1
move remove, accumulate, iterate to itertoolz