Don't add a node to empty graphs in live console.
Merge pull request #1944 from nawroth/2.0-maint

Don't add a node to empty graphs in live console.
Add support for parsing autocommit clause
Add autocommit information to AbstractQuery by introducing new AutocommitQuery

o Introduce PipeInfo in ExecutionPlanBuilder to track this info as a replacement for PipeAndIsUpdating
Evaluate expression to compute autocommit batch size

o Refactored QueryState to be able to instantiate it without collecting statistics
Reject negative autocommit batch size and use default size for null expressions
Move semantic checking of autocommit to the AST
Move AUTOCOMMIT to the beginning of a Query
Move semantic check of autocommit to AST from ExecutionPlanBuilder
Added commitAndRestartTx to QueryContext
Fix license headers
Fix warning: Union is now a sealed trait
Add QueryContext.isOpen() and use it from ClosingIterator
Only set labels if there are some in CreateNode()
Fixed counting in AutoCommitQueryContext and enabled acceptance tests for autocommit
Prevent execution of autocommit queries in open transactions

o Introduces TransactionInfo to clean up passing of tx and related objects to execution plans
Make Cypher aware of queries that are executed from REST server
Add CypherCompiler.isAutoCommit() and expose via ServerExecutionEngine
Add PrefetchingIterator.peek()
Expose autocommit via new transactional endpoint