Fix/remove default engine config

This is what I refer to in issue #577.

Commit message of the actual work commit:

    Remove default engine configuration:

    Default engine configurations are configurations that are
    automatically sent to every engine. This makes no sense, because
    each engine will have its own configuration.

    An example would be a template engine that has a template object
    inside it. The template object gets sent the default configuration.

    The default configuration contains two keys - environment and
    location - which either means nothing to the template object, or
    it means something probably different.

    Instead, these should be sent as attributes to the engines. They
    can be configured in the Engine role and automatically fed. Thing
    is, I couldn't find anything that actually uses them and needs
    them, so I removed it completely.