Destroy file selection dialogs after use - fixes a memory leak as well as a gtk bug that vim triggers when editing gcode files

plater.py

@@ -374,6 +374,7 @@ class stlwin(wx.Frame):
         if(dlg.ShowModal() == wx.ID_OK):
             name = dlg.GetPath()
             self.writefiles(name)
+        dlg.Destroy()
 
     def writefiles(self, name):
         sf = open(name.replace(".", "_") + ".scad", "w")
@@ -401,6 +402,7 @@ class stlwin(wx.Frame):
                 self.load_stl(event, name)
             elif (name.lower().endswith(".scad")):
                 self.load_scad(event, name)
+        dlg.Destroy()
 
     def load_scad(self, event, name):
         lf = open(name)

projectlayer.py

@@ -163,7 +163,7 @@ class setframe(wx.Frame):
             print len(layers[0]), "layers found, total height", layers[1]*len(layers[0]), "mm"
             self.thickness.SetValue(str(layers[1]))
             self.layers=layers
-        
+        dlg.Destroy()
 
     def startdisplay(self,event):
         self.f.Raise()