V1.4.2 pre release

This merge request adds the following changes ahead of a new release of bessyii_devices

1. Corrects a bug with the undulator device so that internal signals are not used. This is still missing better logic to deal with small moves of the undulator...
2. Corrects a bug in the valve device so that it always changes it's internal state even if the valve is opened or closed by some other application, not bluesky