Filter out properties that are the same as their default value

[vincentfretin]

In getComponentClipboardRepresentation filter out properties that are the same as their default value, and modify the propertyRowDefined class calculation to the same to have the property in white if it's different from the default value.

This is continuation of #797 for the copy component to clipboard button where I fixed the serialization logic but didn't keep the filtering out default value logic.
That PR fixes that and also fixes applying the correct color to the property label, white means the property is defined and is different from the default value, otherwise it's gray.

Steps to reproduce the issue:

• select the yellow sphere
• click on the geometry component,
• radius is at 1 (the default) and is gray
• change radius to 2
• change it back to 1
• the radius property is white but should be gray, also the copy to clipboard shows geometry="primitive: sphere; radius: 2" instead of the expected geometry="primitive: sphere"