Move install-prefs to Ansible

I never ended up moving to this installation system, did I?

config/automatrop/roles/desktop_environment/tasks/main.yml

@@ -1,4 +1,4 @@
-- name: Ensure directories for theme are present
+- name: Ensure directories for desktop applications are present
   file:
     state: directory
     path: "{{ ansible_user_dir }}/{{ item }}"
@@ -153,6 +153,16 @@
   tags:
     - color
 
+- name: Enable user services
+  systemd:
+    name: "{{ item }}"
+    state: started
+    enabled: yes
+    scope: user
+  loop:
+    - pulseaudio
+    - mpd
+
 # TODO bar (might change bar in the future, so...)
 # TODO highlight (there IS a template but the colors look different from vim and mostly the same from when there's no config)
 # TODO https://github.com/makuto/auto-base16-theme ? :P