Added the `scripts` option, which takes an array of files and inserts script tags with src attributes in the styleguide template.

As a side effect assets can now be loaded using the shorthand `//` for `http` or `https`.
Refactor the logic for rendering results iframes so it's in the external scripts file instead of the template.
Move the result iframe resizing logic into the scripts file.
Move the navigation folder toggling logic into the scripts file.
Clean up template indentation.
Merge pull request #64 from EvilOatmeal/50-result_output_should_not_contain_or_require_any_logic

Fixes for "#50 Result output should not contain or require any logic"
Merging in changes from #64