Add Error Boundary (has componentDidCatch method) to handle WebGL errors and display an informative message. 

- implements welcome to the preview modal, and unsupported browser modal.
- will need assets updated in Jan.

* Implement GH-830: Add coming soon tooltips

This implements coming soon tooltips for:
* the small stage size
* save, load and language

It also creates the component that can be copied over into the paint editor for use there as well.

Lastly, this does a small refactor on the full screen implementation to include multiple small screen sizes too.

Closes #1073

Closes #1076

Localizes the pen extension:
- loads all pen locale information - may want to consider dynamically loading locales later.