small fix if error happens inside thread execution, then pass correct error_info to display

command imort_svg was using self  instead self.app wrong object

Fix in svgparse for rotate regexp and division by zero problem.
Linestring  need at least 2 points  within very small arcs.
In svg  rect x and  y are optional , they are  0 by default.
Ignore transformation for  unknown kind.
Strip spaces  for  ptliststr In parse_svg_point_list to avoid parsing errors.

tclCommands/TclCommand.py

@@ -388,7 +388,11 @@ class TclCommandSignaled(TclCommand):
             return self.output
 
         except Exception as unknown:
-            error_info=sys.exc_info()
+            # if error happens inside thread execution, then pass correct error_info to display
+            if self.error_info is not None:
+                error_info = self.error_info
+            else:
+                error_info=sys.exc_info()
             self.log.error("TCL command '%s' failed." % str(self))
             self.app.display_tcl_error(unknown, error_info)
             self.raise_tcl_unknown_error(unknown)