Space in path fix

Same issue as https://github.com/mapbox/node-mbtiles/pull/45. Not a critical bug but an annoying one if your config insists on having a space in your development path, as mine does.

- use querystring's unescape() function on uri.pathname in tilelive.auto() and tilelive.info()
- added test for loading mbtiles from a path with a space in it
- all tests passing locally

![image](https://cloud.githubusercontent.com/assets/31717/5058980/43406bae-6cd8-11e4-818f-4246dfb184e1.png)