This end was not detected as connected by the IsDangling method.
Fix incorrect cleaning of dangling tracks in track cleaner.
Remove also a dead code.
The merge co-linear track segments is still full bugged in track cleaner.
Fixes a few commit issues based on the std:: rework. Add an option to
delete tracks fully in pads and makes merge tracks smarter
Fixes: lp:1787190
* https://bugs.launchpad.net/kicad/+bug/1787190