Community Edition 4.2.4-rc1 Release Candidate 1

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge remote-tracking branch 'origin/candidate-4.2.4' into closedown-4.2.x

Conflicts:
	version.cmake

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>