Remove object schema type system

Since libweave no longer semantically parses command/state definitions
and validates commands and states, there is no need for this extra
code.

BUG: 25841230
Change-Id: I53dfab20db8c97b621c07fe234a7b3c6da7325bb
Reviewed-on: https://weave-review.googlesource.com/1660
Reviewed-by: Vitaly Buka <vitalybuka@google.com>
35 files changed