Don't re-install pip from pip every run.

I think having a recent pip is fine. If we run in to problems, we can go back,
but I think we're mainly just wasting effort here.

Change-Id: Ic5f2d49b2002393e1f9b048472266c0a00225110
Reviewed-on: https://review.openstack.org/10963
Approved: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Tested-by: Jenkins

modules/pypimirror/manifests/init.pp

@@ -13,7 +13,7 @@ class pypimirror ( $base_url,
   }
 
   package { 'pip':
-    ensure => latest,  # okay to use latest for pip
+    ensure => present,
     provider => 'pip',
     require => Class[pip]
   }