Remove object schema parsing in CommandDefinition

The only thing we now care about in CommandDefinition is the
"minimalRole" field. Everything else is a black-box which we just
forward to the server without any semantic parsing.

Also completely removed command visibility support since it no
longer applies to trait/component model.

BUG: 25841230
Change-Id: Ie8fff57ffada289caa7876c2a53150bb116fd65b
Reviewed-on: https://weave-review.googlesource.com/1617
Reviewed-by: Vitaly Buka <vitalybuka@google.com>
25 files changed