Add simple playbook task for upgrading servers

We want to treat our servers as cattle; hopefully when this is fleshed out a bit more, it can accomplish the job without too many casualties.

roles/common/templates/pacman.conf.j2

@@ -22,7 +22,7 @@ HoldPkg      = pacman glibc
 Architecture = auto
 
 # Pacman won't upgrade packages listed in IgnorePkg and members of IgnoreGroup
-IgnorePkg    = linux linux-headers linux-hardened linux-hardened-headers linux-lts linux-lts-headers
+#IgnorePkg   =
 #IgnoreGroup =
 
 #NoUpgrade   =