Revert "Changed seneca dependency to 0.5.18 since it is now on github"
Revert "Changed seneca dependency to 0.5.18 since it is now on github"

This reverts commit 01bacbdfa9395bd1d6d56120c3e279c127d19ee5.

KristinaMatuleviciute/seneca-examples,mirceaalexandru/seneca-examples,KristinaMatuleviciute/seneca-examples,mirceaalexandru/seneca-examples,rjrodger/seneca-examples,andfaulkner/seneca-examples,rjrodger/seneca-examples,andfaulkner/seneca-examples,jakepruitt/seneca-examples