skel: purge KDE/Breeze leftovers, add proper GNOME light blue Antergos theme

- Removed KDE/Breeze gtkrc, gtkrc-2.0, .gtkrc-2.0, colors.css,
  window_decorations.css, SVG assets, antergos-log-tool.desktop
- Fixed .bashrc: dropped exo-open fallback (XFCE)
- Fixed firefox.desktop: removed dead antergos.com URL
- Fixed user-commands: calamares -> cnchi
- Fixed PKGBUILD maintainer email
- Fixed wallpaper gschema override path
- Added proper light blue (#1d90cd) GTK3/GTK4 user CSS
- Added Antergos-NeXT GNOME Shell theme with dark panel
- Wired shell theme via gsettings + dbus-launch in chroot
- Added out/ and work/ to .gitignore

airootfs/root/antergos-skel-liveuser/src/etc/skel/.config/gtk-3.0/settings.ini

@@ -1,16 +1,7 @@
 [Settings]
-gtk-application-prefer-dark-theme=true
-gtk-button-images=true
-gtk-cursor-theme-name=Breeze_Light
+gtk-theme-name=Adwaita
+gtk-application-prefer-dark-theme=false
+gtk-font-name=Cantarell 11
 gtk-cursor-theme-size=24
-gtk-decoration-layout=icon:minimize,maximize,close
+gtk-decoration-layout=:
 gtk-enable-animations=true
-gtk-font-name=Noto Sans,  10
-gtk-icon-theme-name=breeze-dark
-gtk-menu-images=true
-gtk-modules=colorreload-gtk-module:window-decorations-gtk-module
-gtk-primary-button-warps-slider=true
-gtk-sound-theme-name=ocean
-gtk-theme-name=Breeze
-gtk-toolbar-style=3
-gtk-xft-dpi=98304