Language Packs: Many many fixes such as:

- Add a "Update Translations" stand-alone button to the updates page
- Shift Language feedback to before update process completion action links & limit the verbosity of output (name + success/errors)
- Simplify/combine the language update descriptive string to only include a plugin/theme name
- Properly handle cache clearing after language updates to prevent langs being repeditively updated
- Display a "All items up to date" string when there's nothing to do
- Reduce the 'Connection Information' from a <h2> to a <h3> to remove duplicate h2's and screen icons from update screens
- Fix the Direct filesystem method not being used for Language updates because WP_LANG_DIR doesn't exist (check it's parent for writable instead)
See #18200, #22704


Built from https://develop.svn.wordpress.org/trunk@25806


git-svn-id: http://core.svn.wordpress.org/trunk@25718 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/css/wp-admin.css

@@ -6636,6 +6636,14 @@ body.iframe {
 	height: 98%;
 }
 
+/* Upgrader styles, Specific to Language Packs */
+.lp-show-latest p {
+	display: none;
+}
+.lp-show-latest p:last-child,
+.lp-show-latest .lp-error p {
+	display: block;
+}
 
 /* - Only used once or twice in all of WP - deprecate for global style
 ------------------------------------------------------------------------------*/