WIP: Create telemetry scheduler.
GUI works, as does saving and loading files.
Currently does not change settings because there is no method for universal
settings changes.
Added copy/paste functionality.
Added frozen table row, for displaying telemetry rate required.
Updated TelemetryScheduler dependencies.
Reordered telemetryschedulergadgetwidget header file.
Added support for setting metadata.
Removed commented code.
Solved double slot problem. Qt automatically connects slots of the name
on_bnFooBar_clicked, so connecting them a second time cause the slot to
be called twice for every signal event.
Added default row, and configured current row to stay updated when metadata
updates.

In addition, blank spaces now represent the default data rate, and when
clicking "Apply" the default value is sent instead of 0.
Fixed indentation issues.
Renamed frozen table with copy-paste class.
Zeros are no longer acceptable input values.
Fixed bandwidth calculations. Now they use the default UAVO metadata
when the cell is empty.
Attempt at deleting cells. Works moderately well, but has a weird bug by
    which a cell must be clicke on after it has been deleted.
Prevent cursor selection of "Default" and "Current" columns.
Added +/- buttons for adding and removing columns.
Provided double-click functionality for changing header text.
Change import method to not fill cells with default value, but to instead
leave them blank.
Import method no longer uses previous values for subsequent column entries.