"can not" => "cannot"
Ensure transaction closed on execution error.

Scope of try block was too small to catch exceptions thrown
  during schema modification operations.
Remove default messages from StatusCode.

Now errors require an exception, and the exception should include a message.
Avoid low-value duplicate text in messages sent to the user.
Add new mapping from CouldNotCreateConstraintException to COULD_NOT_CREATE_CONSTRAINT.
Change assumptions about setting property with bad value - this is user-recoverable.
Fix warnings reported by PMD.
Fixes docs build
Document keep alive and include new timeout in response

o Report new expire time after refreshing transaction timeout
o Due to streaming of results the new expiry time cannot be set in the header
o Updates documentation
o Ensure rollbackSuspended is called with a minimum timeout of 500 ms
o Adds sleep(3000) to two tests due to textual timestamp formats only having seconds resolution
o Use RFC1123 format similar to established HTTP Expires header