[TelemetryScheduler]: Four fixes:

1) Added save button to metadata dialog.
2) Fixed import bug which put values in the wrong column.
3) Fixed import bug which prevented values from being updated because they
could not successfully be converted from strings to numbers.
4) Fixed frozen bar geometry updates when removing columns.
Set apply buttons to expert-only.
Merge pull request #885 from kubark42/telemetry-scheduler-fixes

TelemetryScheduler fixes