News: serial motions, user limits; Debian-10 upgrade

• Serial motions (P06, P08): it was requested to serialize combined motions, e.g. 2 axes operated through the same controller. Or two VmExecutors operate the same physical devices, like the opening and the center of a slit

• User limits (P06, P08): it was requested to implement a way to restore BL-official motor limits after users have changed it.

  It was proposed to implement this feature on the Tango server level according to the policy to gather all relevant information in the Tango servers, allowing PyTango applications, spec and online to co-exist with Sardana. Attributes: unitLimitrMaxExpert, -min, commands: copyExpertLimitsToUserLimits, copyUserLimitsToExpertLimits

  The other proposal was to use the Sardana 'dial' feature.

• Extended mvsa (P23): added options stepssa, stepcssa and stepmssa for P23. Reason: SSA has less restrictions on the signal quality.

  Some testing to be done before general roll-out.

• Debian-10 upgrade
  • Debian-10 is ready, tests passed
  • Install Tango 9.3, tests passed
  • Install python3-sardana, done
  • python2/python3 compliance, done
  • so far 20 Debian-10 hosts installed