Remove some useless spacers, and do not force some widgets to have a to
large size (by removing empty areas).
Work in progress: one panel is still too big.
Previous the cross-probing options were mixed between sending and
receiving cross-probe events. This clarifies so that all of the pcbnew
cross-probe options deal with whether the cross-probe is seen in pcbnew
and all of the eeschema options deal with seeing the event in eeschema.
Also updates the wording in the options panels to be the same where
possible and adds tooltips
Fixes https://gitlab.com/kicad/code/kicad/issues/11454