Check for null and don't had bad data
Handle empty blob reads
Failing blob test
Don't scan outside of the subspace
Test various sizes
Test remaining methods. Writing into middle of blob apperas broken.
Truncate before write to ensure exact blob contents
Restore getChunkAt but compare raw byte arrays instead.
Code cleanup, more final, remove unnecessary casting and verbose comments
merge nathanlws: Blob layer fixes

Merge pull request #1384 from nathanlws/sql-layer/blob-layer-fixes
https://github.com/FoundationDB/sql-layer/pull/1384