added missing icons

changed gear icon to columns icon

ProjectLifer.py

@@ -18,7 +18,7 @@ class ProjectLiferFrame(Frame):
         self.frame_actionbuttons = Frame(self)
 
         photo_folder = PhotoImage(file="data/folder.png")
-        photo_gears = PhotoImage(file="data/gears.png")
+        photo_gears = PhotoImage(file="data/columns.png")
 
         self.button_choosedirectory = Button(self.frame_actionbuttons, compound=TOP, text='Verzeichnis wählen', image=photo_folder, command=self.askdirectory)
         self.button_choosedirectory.image = photo_folder