Examples: COPC test does not support attributes with spaces in their name

Summary

The bindDropDown helper in giro3d\examples\widgets\bindDropDown.js does not build its HTML <option> elements correctly. As a result, if an option has non-word characters as an ID (space, quotes etc.) it will not behave as expected.

Steps to reproduce

1. Open the COPC example with a COPC file that has attributes with spaces in it
2. Choose one of those attributes as coloring attribute
3. See the error in the console. For instance, selecting "height above ground" results in error "attribute 'height' is not supported in this source". This is because the build HTML looks like:

<option value="height" above="" ground="">height above ground</option>

Expected behaviour

The attribute should be selected.

Actual behaviour

It crashes.

Informations

• Giro3D version: ...
• Browser (Firefox, Chrome, Opera, Safari...) and version: ...
• OS (Linux, MacOS, Windows...)

Screenshots

/