add spectacle config, add spotify, fix cinny video playback with gstreamer

refactor some stuff to look nicer and have more structure too

modules/nixos/system/gstreamer/default.nix

@@ -0,0 +1,50 @@
+{
+  config,
+  lib,
+  pkgs,
+  namespace,
+  ...
+}:
+with lib;
+with lib.${namespace};
+let
+  cfg = config.${namespace}.system.gstreamer;
+in
+{
+  options.${namespace}.system.gstreamer = with types; {
+    enable = mkBoolOpt false "Whether or not to enable gstreamer support.";
+  };
+
+  config = mkIf cfg.enable {
+    environment.systemPackages = with pkgs; [
+      # Video/Audio data composition framework tools like "gst-inspect", "gst-launch" ...
+      gst_all_1.gstreamer
+      # Common plugins like "filesrc" to combine within e.g. gst-launch
+      gst_all_1.gst-plugins-base
+      # Specialized plugins separated by quality
+      gst_all_1.gst-plugins-good
+      gst_all_1.gst-plugins-bad
+      gst_all_1.gst-plugins-ugly
+      # Plugins to reuse ffmpeg to play almost every video format
+      gst_all_1.gst-libav
+      # Support the Video Audio (Hardware) Acceleration API
+      gst_all_1.gst-vaapi
+    ];
+
+    environment.sessionVariables.GST_PLUGIN_SYSTEM_PATH_1_0 =
+      lib.makeSearchPathOutput "lib" "lib/gstreamer-1.0"
+        (
+          with pkgs.gst_all_1;
+          [
+            gstreamer
+            gst-plugins-base
+            gst-plugins-good
+            gst-plugins-bad
+            gst-plugins-ugly
+            gst-libav
+            gst-vaapi
+          ]
+        );
+  };
+
+}