Travis fixes
Add support for loading over HTTP, including support for Range headers.
First pass at exploded form.
Various fixes for Python 2.7 < .4 and Python 3
Python 2.6 fix.
Merge pull request #1 from mdboom/http

Support HTTP requests
Use multiprocessing rather than threading to run the HTTP servers.  This
is *much* faster.
Merge pull request #16 from mdboom/faster-http-testing

Use multiprocessing rather than threading for "test" webservers
Use wheels for numpy and cython.
Merge pull request #17 from mdboom/travis-wheels

Use wheels for numpy and cython.
Improve how "explode" works -- allow for deep linking to blocks inside
of FINF files.
Add a test
Allow referencing of blocks within FINF files.  Greatly increase code coverage.
Python 3 fixes.
Don't allow directly linking to anything but the first block in an
external file.
Make YAML internal references (anchors and aliases) work.
Support external YAML references.
Fix some file closing issues.
Improved laziness on reference resolution.
Minor fixes.