the filled areas can use a hatch pattern (crossing lines) using square holes.
The zone filler removes too small holes (truncated holes) from hatch pattern.
It avoid to create small holes when a hole pattern is truncated by the filled area base shape.
We no longer require this as we calculate the number of segments based
on the maximum deviation rather than fixed numbers.
Fixes: lp:1780518
* https://bugs.launchpad.net/kicad/+bug/1780518
Also includes a bunch of changes to simplifiy the terminology
and unify the copper, non-copper and keepout versions.
Also removes some legacy features:
Removes contol for fill method. If the fill method is currently
segments the dialog will ask if you want to convert to polygons
on OK.
Removes control of boundary resolution. We've done this with trig
since 5.0.
(cherry picked from commit 487aaeb)