Enable CustomElement to handle content manually

[RichiCoder1]

Problem

Currently there is no way to pass raw content into the innerHtml of a CustomElement and have it manually processed.
ex:

<x-markdown>
    Title
    ======

    # Items
    ....
</x-markdown>

Attempted to consume the markdown within the CustomElement is impossible, as Aurelia will attempt to process it.

Solution

Add a Metadata extension which allows you to signal Aurelia that the CustomElement will parse it's inner content it's self.

Recommendations:

Metadata.handlesContentManually();
Metadata.skipProcessingContent();

[t3hprofit]

Metadata.skipContentProcessing(); rolls off the tongue a little easier or Metadata.deferContentCompilation(); possibly

[RichiCoder1]

Defer makes it seem like the engine will still do it at some point. We want complete control with the CustomElement.
Agreed on skipContentProcessing();

[EisenbergEffect]

Use .skipContentProcessing(). You may also want to use this in conjunction with .noView(). It will go out in the next templating release, today or tomorrow.

[RichiCoder1]

Yay :D