Added collapsable group box for the Options section, removed maps_names_from_files since it is available in the 2-gears operator, cleanup and bugfixes

Author: Kos-Design

__init__.py

@@ -1,3 +1,5 @@
+import bpy
+
 bl_info = {
     "name": "Substance Textures Importer",
     "author": "Cosmin Planchon",
@@ -10,21 +12,19 @@
     "tracker_url": "https://github.com/Kos-Design/substance_textures_importer/issues",
     "category": "Node"}
 
-import bpy
+from . functions import menu_func
 
 from . propertygroups import ( StringItem,LinerItem,ShaderLinks, NodesLinks, StmProps)
 
-from . operators import ( NODE_OT_stm_reset_substance_textures,
-                          NODE_OT_stm_move_line,NODE_OT_stm_add_substance_texture,NODE_OT_stm_del_substance_texture,
+from . operators import ( NODE_OT_stm_reset_substance_textures,NODE_OT_stm_del_substance_texture,
+                          NODE_OT_stm_move_line,NODE_OT_stm_add_substance_texture,
                           NODE_OT_stm_surfacing_setup,NODE_OT_stm_fill_names,IMPORT_OT_stm_window)
 
 from . panels import ( NODE_PT_stm_nodes_panel,MATERIAL_PT_stm_material_panel )
 
 from . preferences import (StmAddonPreferences, StmPanelLiner, NODE_UL_stm_list, StmPanelLines,
                             StmChannelSocket, StmChannelSockets,StmShaders, StmNodes,)
 
-from . functions import menu_func
-
 classes = (
     LinerItem,
     StringItem,