Test and fix codebase for jython

[adamhaney]

Currently we're not testing against jython, but being able to run in jython would be really cool because the jython interpreter can run much faster in some situations and would give lispy access to Java libraries.

[adamhaney]

http://www.topbug.net/blog/old/2012-05-27-use-travis-ci-with-jython.html