ENG-4422: Make SnapshotRestore return failure when it partially fails.
Currently returns OPERATIONAL_FAILURE, but that could get renamed after discussion.
ENG-4422: Add two missing places to change the status code.
ENG-4422: Fix a lame accidental negation that broke some tests.
ENG-4422: One small change from izzy.
Merge pull request #430 from VoltDB/ENG-4422-partialsysprocfailure

Eng 4422 Return failure when restore partly fails