Make ropevim pathogen compliant.

Pushing whole repo to ~/.vim/bundle is quite inefficient, but seems to
be the most elegant solution so far. Any better solutions are highly
welcomed.

Fixes #18
Remove docs/todo.txt.

All issues (although rather unintelligible) were moved to the GitHub
Issue Tracker.
Modify README.rst to describe pathogen-based installation.

Also to fix broken rST table.
doc/ not docs/