Node: set correct mime types

As a side effect, this removes all the warnings in the debug console
stating:

> Resource interpreted as script but transferred with MIME type
text/plain.
FCM Editor updation
visaulization updates
visaulization updates
visaulization updates
visaulization updates
visaulization updates
FCM Editor
FCM Editor
Merge branch 'master' of https://github.com/policycompass/policycompass-frontend
visualization updates
visualizations updates
update visualization frontend
visualizations front-end updates
Changed labels
Request Template added
visualizations front-end updates
Fixup 7a5f95eff27c: Remove trailing comma

This isn't allowed in Javascript.
Expose policyCompassConfig as global variable

We need the config in order to allow disabling entire modules in app.js.

If there's a way to do that with dependency injection instead of global
variables, this should be changed.
Load AdhocracySDK as angular service

This is disabled in config.js, as it requires a running Adhocracy
installation.