If N1QL API is used directly, do a runtime check for recursion

As discussed today, if user has directly utilized N1QL() wrapper in event handler, then the recursive mutation check is bypassed as those are enforced by transpiler. Detect such direct use of N1QL() function and do a runtime check to ensure buckets being written to form a directed acyclic graph. This can be cached (using a limited size map) with hash of the statement as key, and result of check as the value of the cache.