Interrupt transaction on disconnect for single query transaction in transactional REST endpoint

o Adds number of transaction interrupts to TransactionMonitor

Signed-off-by: Jakub Wieczorek <jakub.wieczorek@neotechnology.com>
Temporarily ignored two tests that need to be fixed either by kernel or some future Cypher merge
Add X-Transaction-Interrupt header to all requests that create a new transaction

Signed-off-by: Jakub Wieczorek <jakub.wieczorek@neotechnology.com>
Add tests to REST server interrupt handling

o Rename getInterruptHandler() to interruptHandler()

Signed-off-by: Jakub Wieczorek <jakub.wieczorek@neotechnology.com>