merge new pull requests from FlatCAM->master

implement  executing of tasks  inside worker thread
cleanups, reimplement  Isolate/New/OpenGerber as OOP style Shell commands
disable edit  during shell execution,  show   some  progress
add ability for breakpoints in other threads and only if available
add X11 safe flag, not sure what happen on windows

camlib.py

@@ -890,6 +890,26 @@ class Geometry(object):
         """
         self.solid_geometry = [cascaded_union(self.solid_geometry)]
 
+    def export_svg(self, scale_factor=0.00):
+        """
+        Exports the Gemoetry Object as a SVG Element
+
+        :return: SVG Element
+        """
+        # Make sure we see a Shapely Geometry class and not a list
+        geom = cascaded_union(self.flatten())
+
+        # scale_factor is a multiplication factor for the SVG stroke-width used within shapely's svg export
+
+        # If 0 or less which is invalid then default to 0.05
+        # This value appears to work for zooming, and getting the output svg line width
+        # to match that viewed on screen with FlatCam
+        if scale_factor <= 0:
+            scale_factor = 0.05
+
+        # Convert to a SVG
+        svg_elem = geom.svg(scale_factor=scale_factor)
+        return svg_elem
 
 class ApertureMacro:
     """
@@ -3334,6 +3354,54 @@ class CNCjob(Geometry):
 
         self.create_geometry()
 
+    def export_svg(self, scale_factor=0.00):
+        """
+        Exports the CNC Job as a SVG Element
+
+        :scale_factor: float
+        :return: SVG Element string
+        """
+        # scale_factor is a multiplication factor for the SVG stroke-width used within shapely's svg export
+        # If not specified then try and use the tool diameter
+        # This way what is on screen will match what is outputed for the svg
+        # This is quite a useful feature for svg's used with visicut
+
+        if scale_factor <= 0:
+            scale_factor = self.options['tooldia'] / 2
+
+        # If still 0 then defailt to 0.05
+        # This value appears to work for zooming, and getting the output svg line width
+        # to match that viewed on screen with FlatCam
+        if scale_factor == 0:
+            scale_factor = 0.05
+
+        # Seperate the list of cuts and travels into 2 distinct lists
+        # This way we can add different formatting / colors to both
+        cuts = []
+        travels = []
+        for g in self.gcode_parsed:
+            if g['kind'][0] == 'C': cuts.append(g)
+            if g['kind'][0] == 'T': travels.append(g)
+
+        # Used to determine the overall board size
+        self.solid_geometry = cascaded_union([geo['geom'] for geo in self.gcode_parsed])
+
+        # Convert the cuts and travels into single geometry objects we can render as svg xml
+        if travels:
+            travelsgeom = cascaded_union([geo['geom'] for geo in travels])
+        if cuts:
+            cutsgeom = cascaded_union([geo['geom'] for geo in cuts])
+
+        # Render the SVG Xml
+        # The scale factor affects the size of the lines, and the stroke color adds different formatting for each set
+        # It's better to have the travels sitting underneath the cuts for visicut
+        svg_elem = ""
+        if travels:
+            svg_elem = travelsgeom.svg(scale_factor=scale_factor, stroke_color="#F0E24D")
+        if cuts:
+            svg_elem += cutsgeom.svg(scale_factor=scale_factor, stroke_color="#5E6CFF")
+
+        return svg_elem
 
 # def get_bounds(geometry_set):
 #     xmin = Inf