Update support files.
Add test case for package exports.
Add test case for Descriptor.
More test cases for Descriptor.
Test case for Link.
More test cases for Link.
Add test case for lrdd middleware.
More test cases for lrdd middleware.
Test cases for content negotiation.
Remove old vows tests.
Fix Travis CI for Node 0.6.
Disable Travis CI builds on Node 0.6.
Add dependency on multihash.