Ensure mosh, screen, and tmux are available

These are great tools that are even better together and make remote administration an absolute delight.
servo · bors-servo · Sep 12, 2016 · Apr 22, 2016 · Apr 22, 2016 · Aug 19, 2016
commit 1999a8eb48dd1dc912b9f96f87f6bf96dd9498b7
diff --git a/admin/init.sls b/admin/init.sls
@@ -0,0 +1,10 @@
+admin-packages:
+  pkg.installed:
+    - pkgs:
+      - tmux
+      {% if grains['os'] != 'MacOS' %}
+      - mosh
+      - screen # Installed by default on OS X
+      {% else %}
+      - mobile-shell
+      {% endif %}
diff --git a/top.sls b/top.sls
@@ -2,6 +2,7 @@
 
 base:
   '*':
+    - admin
     - common
     - salt.common