Should be harmless on Python 3.4.

Closes #149.

Add support for Python geo interface, too.

Closes #146.

Also remove the double tag update test, which is crashing. I'll
add back in a new branch.

For #145.

This wraps up #117 for good.

For #145.

Also add a couple tests that had been missed.

For #137.

Rio entry point

For #137.

Refactor to avoid unneeded numpy imports.

Closes #140.

Fairly easy because Numpy methods accept either strings like
`'uint8'` or types like `np.uint8` as dtypes. So do Rasterio
methods now.

Closes #139.

Making and installing from an sdist isn't trivial, needs a little
more thought.

This shakes out packaging problems as well as library bugs.

See #135.

Tests that installed from an sdist would have caught this. Should
look into that.

Closes #135.

New test layout

Merge command.

Remove test data from sdists. Check for it when running tests and
direct users to download location. No automated download... I don't
expect many users to be running the tests from an sdist.

Closes #133.

Testing requires the 'six' package for StringIO

For #128.

Also tests for the CLI.

Much refactoring on rio bounds and shapes was done
here. Profiling needs to be done to see what can be done
to speed it up.

Closes #127.