Property sheets use inconsistent case for labels

[Stevenic]

Describe the bug

Our use of case for property labels is all over the map. We should use consistent case for property labels.

[cwhitten]

We need to conform to Sentence case, however the inconsistency in your example comes off of the component schemas.

[luhan2017]

Transferring this issue to sdk, this needs the component schema update. @vishwacsena for your awareness.