rasdaman does not show correct error on multiple write transactions

[Alex Dumitru]

A rasdaman instance without the lockmanager enabled should throw "Write transaction in progress" error when two write transactions are executed concurrently.
Instead it returns transfer failed, i.e.
RasdamanHelper2::updateImage():image update failed: Exception: Transfer Failed
rasimport::main(): Exception: Transfer Failed

[Dimitar Misev]

I can't reproduce this, tried with two rasql and rasql+rasimport mixed commands, e.g.

rasql -q "insert..." &
sleep 0.5
rasimport -f ...

and always get a "RasManager Error: Write transaction in progress, please retry again later."