Minor fix to apply mag field
Fixing stupid bug in save task for array.
Fixing bugs in agilent PNA driver and PNASweepTask.
Save faulty checks in save array and array_extrema. Add a comment in database.
Fix issue in PNA tasks: the use of ':' caused issue in the monitor (Python string formatting), so moved from ':' to '_' which more consistent with everything else.
Fix minor disply quirk in RootTask.
Fix issue in check of PNA sweep task.
Merge remote-tracking branch 'origin/feature-database' into feature-task-interface

Conflicts:
	hqc_meas/tasks/tasks_instr/pna_tasks.py