Issue#591 Generated SQL from WITH-CTEs does not include a table ident…

where we are calling getException() and seeing a null value.
Because we access these without synchronization, we need to use volatile.

can throw OUT_OF_MEMORY error

so that it doesn't cause an exception on travis, although given the
exceptions it is catching, I can't see what it is trying to test

shows up as random failures in the TestMVStore.testFastDelete test case

Make it possible to create a cluster without using temporary files.

"Connection is broken: "unexpected status 16777216" [90067-192]" message when using older h2 releases as client

Instead use Java pipes.