updated comments
forgot here; renamed option as direction
wrap the line
refining query.rst
forgot to add replace in __all__ lol
reviewed the doc of select again
added full usage for each main func in query.rst
reviewed the query.rst again
Use unicode in all internals

Makes the whole thing compatible to Python 3.

Also added a feature detection to db.py so that the tests run on
Python 3 (which does not have izip).

Fix #37.
Encode to bytes on output

This maintains backward compatibility. Since the main use case of
MoSQL is to feed the output directly to database APIs, this should
be the better approach.
Make raw and param inherite unicode instead

Also add "print" to doctests so that they can behave the same on
both Python 2 and 3.
More Python 3 compatibility fixes
Need to include print_function to make tests pass
Do not encode on output