Relax tests for Connection header
Use "~version" instead of "^version" in package.json

Otherwise you can't install this package in old (pre-node-v0.10.16)
versions of npm.

See:
http://fredkschott.com/post/2014/02/npm-no-longer-defaults-to-tildes/
http://www.reddit.com/r/node/comments/1wo7n4/people_misunderstand_and_and_semver_in_nodejsnpm/