Full re-write of spiral vase (#3091)

* Practically full re-write of spiral vase
- Adds transition out to prevent sharp edge at the top of spiral vase.
- Adds XY interpolation
- Adds option to turn XY interpolation on/off

* - Increasing E to 5 decimal digits (I observed uneven flow with less than that)
- Excluding all travel moves (I saw a bug where somehow we ended up with travel moves within the print so excluding all travel moves)

* - max_xy_smoothing is now configurable, default is 200% of nozzle_diameter
- fixed no-op travel moves in the middle of spiral that now show up as defects when Smooth Spiral is enabled!

* - Avoiding namespace pollution
- Fixing dist_XY == 0 bug

---------

Co-authored-by: Andrew Boktor <aboktor@microsoft.com>
Co-authored-by: SoftFever <softfeverever@gmail.com>

src/libslic3r/PrintConfig.hpp

@@ -1120,6 +1120,8 @@ PRINT_CONFIG_CLASS_DERIVED_DEFINE(
     ((ConfigOptionFloat,              skirt_speed))
     ((ConfigOptionFloats,             slow_down_layer_time))
     ((ConfigOptionBool,               spiral_mode))
+    ((ConfigOptionBool,               spiral_mode_smooth))
+    ((ConfigOptionFloatOrPercent,     spiral_mode_max_xy_smoothing))
     ((ConfigOptionInt,                standby_temperature_delta))
     ((ConfigOptionInts,               nozzle_temperature))
     ((ConfigOptionBools,              wipe))