testing/clipper: new aport

https://sourceforge.net/projects/polyclipping/
Polygon, line clipping and offsetting library
7 jobs for !2741 with clipper in 1 minute and 34 seconds (queued for 1 second)
detached
Status Job ID Name Coverage
  Lint
passed #31266
docker-alpine x86_64
lint

00:00:33

 
  Build
passed #31271
docker-alpine ci-build aarch64
build-aarch64

00:00:42

passed #31272
docker-alpine ci-build armv7
build-armv7

00:00:42

passed #31270
docker-alpine ci-build ppc64le
build-ppc64le

00:01:00

passed #31269
docker-alpine ci-build s390x
build-s390x

00:00:34

passed #31268
docker-alpine ci-build x86
build-x86

00:00:30

passed #31267
docker-alpine ci-build x86_64
build-x86_64

00:00:28