syncbase: Enforce ACL spec on sync RPCs.
Syncgroup Manager RPCs now check permissions according to the Syncbase
ACL specification document, including recursively checking for Resolve
access where appropriate.
Documented status of Syncbase-to-Syncbase RPC permissions better.
Added other sanity checks - Collection existence and Read permission at
syncgroup create/join, prevent removing self from syncgroup ACL.
Added permission spec tests for client-to-Syncbase Syncgroup Manager and
12 files changed