[ansible] remove unused imac playbook

ansible/imac.yml

@@ -1,12 +0,0 @@
-- hosts: all
-  tasks:
-    - name: install sleepwatcher
-      homebrew_cask: name=sleepwatcher state=installed
-
-    - name: install smcfancontrol
-      homebrew_cask: name=smcfancontrol state=installed
-
-    # TODO Install launchd scripts, etc. for sleepwatcher
-
-    - name: link ~/.wakeup
-      file: src=~/.dotfiles/scripts/kill_imac_hdd_fan.rb dest=~/.wakeup state=link