Fixes #447. Jquery npm version was breaking on newer npm
Shot in the dark -- remove cffi explicit dependency
Revert "Shot in the dark -- remove cffi explicit dependency"

This reverts commit 4cfe3d5bcc06ab6004401cd7cd0f88732ddb6586.
Attempt to fix travis bcrypt issue.
Merge pull request #466 from girder/npm-install-error

Fixes #447. Jquery npm version was breaking on newer npm