editor.php: only use gethostbyaddr on new entries

git-svn-id: https://plugins.svn.wordpress.org/gwolle-gb/trunk@1028915 b8457f37-d9ea-0310-8a92-e5e31aec5664
posthandling.php: only use gethostbyaddr on new entries

git-svn-id: https://plugins.svn.wordpress.org/gwolle-gb/trunk@1028917 b8457f37-d9ea-0310-8a92-e5e31aec5664
class entry: only use gethostbyaddr on new entries

git-svn-id: https://plugins.svn.wordpress.org/gwolle-gb/trunk@1028918 b8457f37-d9ea-0310-8a92-e5e31aec5664