Fix prev feature commit, Do not require aptitude to use apt commands in the apt…

Fix prev feature commit, Do not require aptitude to use apt commands in the apt module, only needed when upgrading.

library/packaging/apt

@@ -233,6 +233,8 @@ def upgrade(m, mode="yes", force=False):
         check_arg = '--simulate'
     else:
         check_arg = ''
+
+    apt_cmd = None
     if mode == "dist":
         # apt-get dist-upgrade
         apt_cmd = APT_GET_CMD
@@ -291,10 +293,10 @@ def main():
     global APT_GET_CMD
     APT_GET_CMD = module.get_bin_path("apt-get")
 
-    if not APTITUDE_CMD:
+    p = module.params
+    if not APTITUDE_CMD and p.get('upgrade', None) in [ 'full', 'safe', 'yes' ]:
         module.fail_json(msg="Could not find aptitude. Please ensure it is installed.")
 
-    p = module.params
     install_recommends = p['install_recommends']
 
     try: