WIP: Document usage examples

[pratapvardhan]

• [ ] Templates using child / custom elements
• [ ] Elaborate example for slots
• [x] Would like to set data via fetch / Promises inside the template. For example, <bs-card url="./data?"><bs-card>. I should be able to set data variable in the script tag after promise is completed?
• [ ] Add example for integrating one of (vega-lite, d3 barchart) to element node using props.
  • [ ] Explicitly mention using e.target in the example
  • [ ] Document anti-patterns
• [x] Dynamic creation / custom element creation on the fly alternatives to
  • [x] $('elsewhere').html('<main-element" value="update world"><main-element>')
  • [x] document.createElement('main-element') probably?

    
    <main-element" value="hello"><main-element>
    <main-element" value="world"><main-element>

```javascript
$('elsewhere').html('<main-element" value="update world"><main-element>')

[sanand0]

1954148: Documents dynamic creation of elements

[pratapvardhan]

Added: Would like to set data via fetch / Promises inside the template. For example, <bs-card url="./data?"><bs-card>. I should be able to set data variable in the script tag after promise is completed? Let me know if this isn't clear.