Remove extraneous files; update themes submodule

- A preconfigured config.ini is probably not useful these days. There's
  an options menu now.
- Removed gs4 background - already in vanilla pack.
- Themes submodule should probably be configured to track master. Meh.
  Submodules can be so finicky. It probably doesn't belong in this repo
  anyway - it should be in the vanilla repo (currently invisible).

.gitlab-ci.yml

@@ -123,7 +123,6 @@ build windows i686:
     mkdir base
     mkdir base/themes
     cp -a ../base/themes/default base/themes/
-    cp -a ../base/config.ini base/config.sample.ini
     cp -a ../base/serverlist.txt base/serverlist.sample.txt
 
 # Miscellaneous files

base/config.ini

@@ -1,10 +0,0 @@
-theme = default
-blip_rate = 1
-blank_blip = false
-default_music = 50
-default_sfx = 50
-default_blip = 50
-discord = true
-ic_scroll_down = false
-; master = master.aceattorneyonline.com
-; ooc_name = Phoenix

base/themes

@@ -1 +1 @@
-Subproject commit 49cc1265f55e2939248bc1eeb6be93a8a03b9853
+Subproject commit 4b8496e7b6b0926fb9f4f6f13d86cd1da31b047a