add custom image picker

src/FileList.tscn

@@ -0,0 +1,19 @@
+[gd_scene load_steps=4 format=2]
+
+[ext_resource path="res://src/FileList.gd" type="Script" id=1]
+[ext_resource path="res://assets/icon_parent_folder.png" type="Texture" id=2]
+[ext_resource path="res://assets/icon_folder.png" type="Texture" id=3]
+
+[node name="FileList" type="ItemList"]
+anchor_right = 1.0
+anchor_bottom = 1.0
+max_columns = 4
+fixed_icon_size = Vector2( 160, 160 )
+script = ExtResource( 1 )
+__meta__ = {
+"_edit_use_anchors_": false
+}
+root_dir = "res://assets/artworks"
+folder_texture = ExtResource( 3 )
+parent_folder_texture = ExtResource( 2 )
+[connection signal="item_selected" from="." to="." method="_on_FileList_item_selected"]