Remove some apostrophes from comments to work around puppet-mode bug.

The Emacs puppet-mode misinterprets apostrophes in comments and think
they are string quotes.  This breaks end-of-defun (C-M-e).  By not
having unmatched apostrophes in comments in class and define bodies,
we work around that.

This also fixes a genuine misspelling ("it's" instead of "its").

This was originally commit 028ff3e2716c in nsc-puppet-utils.

manifests/init.pp

@@ -157,7 +157,7 @@ define xen_domu(
 	    }
 	}
 	"installed": {
-	    # "Installed" means that we don't care if it is running or not
+	    # "Installed" means that we do not care if it is running or not
 	}
 	"stopped": {
 	    xen_domu__::stopped {