Update images in "step by step" pages

[Piralein]

Nodes and Scenes

Update content of the search field

nodes_and_scenes_02_scene_dock.webp
nodes_and_scenes_character_nodes.webp
nodes_and_scenes_nodes.webp

Remove system specific header for consistent look

nodes_and_scenes_03_create_node_window.webp
nodes_and_scenes_04_create_label_window.webp
nodes_and_scenes_10_save_scene_as.webp
nodes_and_scenes_14_select_main_scene.webp

Update from version 3 to version 4

nodes_and_scenes_3d_scene_example.webp

Instancing

Missing Game tab

instancing_2d_scene_select.webp
instancing_ball_instanced.webp
instancing_main_scene.webp
instancing_main_scene_with_balls.webp

Wrong Icon

instancing_ball_scene_open.webp

Missing "Edit Now" feature

instancing_import_and_edit_button.webp

Missing "Edit v" and "Rename" feature

instancing_import_button.webp

New layout

instancing_instance_child_window.webp

"Main" isn't selected

instancing_scene_link_button.webp

First script

New layout

scripting_first_script_add_sprite_node.webp

just didn't like it

scripting_first_script_attach_script.webp

"Search Results" doesn't exist

scripting_first_script_print_hello_world.webp

Update from version 3 to version 4

scripting_gdscript.webp

Signals

New layout

signals_05_add_button.webp

Remove system specific header

signals_14_signals_connection_info.webp

just didn't like it (and 2d should be 2D)

signals_15_scene_tree.webp
signals_16_click_script.webp

Update from version 3 to version 4

signals_18_timer_autostart.webp

[skyace65]

Thanks!