Add more info to tagging instructions

Author: ArturMoczulski

README.md

@@ -133,6 +133,7 @@ This is only for contributors with committer access:
     2. Add record in the `Changelog` section of the `readme.txt`.
     3. Add record in the `Upgrade Notice` section of the `readme.txt`.
     4. Bump the plugin version in `rollbar-php-wordpress.php` in the `Version:` comment.
+    5. Add and commit the changes you made to bump the plugin version.
 2. Tag the new version from the `master` branch and push upstream with `git tag [version number] && git push --tags`.
 3. Update the WordPress Plugin Directory Subversion Repository.
     1. Remove the contents of `trunk/` with `rm -Rf trunk/*`.