Define 'too long' line segments as twice the lenght of smallest.
Should fix microsegemtns for occurrences of 'line segments slightly longer than the minimum' and 'small line segments but longer than 5 micron' occurring together often. Which in turn should fix those microsegments that still cause blobs at least on UM printers.
Don't use zig-zag endpieces when using gradual infill
The endpieces will connect the endpoint of the zigzag pattern up to the last real line along the edge, but this causes massive overlaps when the pattern is used at different densities next to each other for gradual infill.
We _do_ want to enable this however there is a bug in the current implementation. It is checking _all_ the extruders and if `travel_avoid_supports` is enabled on one of the extruders then this feature is enabled for all combing.
This introduces problems for PVA support. If `travel_avoid_supports` is disabled for the PLA extruder but disabled for the PVA extruder the `model_boundary` will contain the boundary for support. As there are many travel moves within/through this model boundary with support area's included there will be many retractions. This is the main cause for https://ultimaker.atlassian.net/browse/CURA-9163.
