Support of inner Sketch features via data-sketch-{feature} attribute

[yakunins]

Similar to issue Using specific data attributes for Sketch.

Feature description
Make some inner Sketch features avaliable in the way like this: <div data-sketch-locked>This group is locked in Sketch</div>

We have already implemented some attributes here → handleSymbolAttributes.js @servicetitan/html-sketchapp/st-dev

So these attributes, that we have been working on (bugs to be found!):

1. data-sketch-constraints="align left, fixed width"
2. data-sketch-rotation="18deg"
3. data-sketch-padding="10px 16px" (with Paddy plugin)
4. data-sketch-spacing="10h 12v" (with Paddy plugin)
5. data-sketch-textlabel="First name"
6. data-sketch-locked=true
7. data-sketch-ungroup=true