Upgrade 3.1.x free auf 3.1.x pro

To upgrade from BlueSpice free 3.1.x to BlueSpice pro 3.1.x (under Linux), follow these instructions:

1. Create backup: Make a database dump and save it together with the complete codebase to another storage location.
2. Patch-update BlueSpice free (optional): Check your current version on the Special: Version page. Compare your version with the current version of BlueSpice free. If you have not installed a relatively current version, apply a patch update.
3. Replace the codebase: Overwrite the codebase of your current version with the new codebase of BlueSpice pro.
4. Start the update:
   1. Open a console and switch tot he installation directory (the level of LocalSettings.php)
   2. Execute: php maintenance/update.php
5. Re-index the search:
   1. Delete search index: php extensions/BlueSpiceExtendedSearch/maintenance/initbackends.php
   2. Create new search index: php extensions/BlueSpiceExtendedSearch/maintenance/rebuildIndex.php --quick
   3. Run jobs: php maintenance/runJobs.php