Fix #38

Explicitly set the instance_path parameter to Flask so that when the app is installed, it doesn't try to write to a privileged directory.
Fix abspath invocation

Previously, this would have created a '~' directory in the current dir. Now, this resolves homedirs first.
Fix typo
python3ify all the things
fix style loading issue
remove grip from requirements
Merge pull request #54 from fly/py3ify

python3ify all the things
Update year to 2014.
Extract default filename constants:

* Move into constants.py
* Add supported_extensions constant
Add the GitHub-supported format extensions.
Update dependencies to latest versions.
Fix print function in Python 2.
Add ability to export to a specific file.
Revert "Add the GitHub-supported format extensions."

This reverts commit 4f67141cfabe99af99434364e13fec91bef291a7.
Fix #58 by adding JavaScript behavior like GitHub does.
Fix #46: Document the --user / --pass arguments
README: Refer to the offline rendering branch in the Access section.
Set version to 2.0.1.
Remove duplicate 'context': context in GitHub renderer.
Fix the headers sent by the GitHub renderer.