wxChoice centers the selection on GTK. So when switching from a
mid-list item to an item at the top, the list is always cut off for
choice lists located on the top toolbar. Using a combobox provides a
drop-down that allows easier access to all elements in the box.
Fixes: lp:1808569
* https://bugs.launchpad.net/kicad/+bug/1808569
Also fixes a bug where nets wouldn't get changed because the
pads weren't changed and so the pad nets would propagate and
wipe out the changed nets on the tracks.
Also includes warning dialogs that pad nets will be changed if the
track nets are.
Fixes: lp:1779854
* https://bugs.launchpad.net/kicad/+bug/1779854
Improve dialog layout and fix UI policy issues with all of the dialog
boxes in the Gerbview and Pcbnew code paths.
Updated the use of component to footprint where appropriate.
File "rules" has instructional text as comments near top.
2) Convert all text files in repo to LF line ending form.
Any checkout done with "rules" in play will convert the working
tree to native line ending, while keeping repo as LF line ending.