Implement the Descriptor Cluster

[andy31415]

Problem

Initial operation and connectivity to a device depends heavly on the other end being able to identify the device type.

We need to implement the Descriptor cluster (section 7.4.6 currently in the CHIP Spec)

Proposed Solution

Implement the new cluster. Likely need incremental implementations since the cluster relies on struct and list data types which are not yet supported by our code generators.

[andy31415]

Document on how to add clusters to CHIP: https://docs.google.com/document/d/1_FoSrDz89QYhIn24m-6oRyabspJujkBP695p_MMhI5M/edit#

[yufengwangca]

This is implemented in #5020