fix(nunjucks): explicitly set autoescaping to off
fix(nunjucks): explicitly set autoescaping to off

The latest nunjucks engine sets this to true, so we now must manually
turn it off again.

Closes #198

angular/dgeni-packages,petebacondarwin/dgeni-packages,angular/dgeni-packages,petebacondarwin/dgeni-packages,petebacondarwin/dgeni-packages,angular/dgeni-packages