updated frontend stack to latest versions (#729)

UPGRADING.md

@@ -1,37 +1,31 @@
 # Upgrading Kimai 2
 
-_Database upgrades are currently ONLY provided for MySQL/MariaDB and SQLite._ 
+_Make sure to create a backup before you start!_ 
 
-Upgrading to the latest available version can be achieved with these commands: 
+Read the [updates documentation](https://www.kimai.org/documentation/updates.html) to find out how 
+you can upgrade your Kimai installation to the latest stable release.
 
-```bash
-git fetch --tags
-git checkout 0.8
-sudo -u www-data composer install --no-dev --optimize-autoloader
-sudo -u www-data bin/console cache:clear --env=prod
-sudo -u www-data bin/console cache:warmup --env=prod
-bin/console doctrine:migrations:migrate
-```
+**Before you leave ...**
 
-There might be more steps required which are version specific and need to be executed after following the above list of commands.
-Read and follow each version info below, otherwise you risk data inconsistency or a broken installation!
-
-And make sure to **create a backup before you start**.
+There might be more steps required which are version specific and need to be executed after [the update](https://www.kimai.org/documentation/updates.html).
+Read and perform EACH version specific task below, otherwise you risk data inconsistency or a broken installation!
 
 ## 1.0 (unreleased)
 
-Follow the normal update and database migration process (see above).
+This release contains several changes, as I still have the goal to stabilize the code base to prevent 
+such "challenges" after 1.0 for a while.
 
-### Apply necessary changes to your local.yaml:
+### Changes for your local.yaml
  
-New permissions are available. If you configured custom permissions in `local.yaml`, you have to add those, otherwise you can't use the new features: 
+New permissions are available. You have to add them to your `local.yaml` ONLY if you use a custom permission structure, 
+otherwise you can't use the new features: 
 - `view_tag` - view all tags
 - `delete_tag` - delete tags
 - `edit_exported_timesheet` - allows to edit records which were exported
 - `role_permissions` - view calculated permissions for user roles
 
 Removed permission:
-- `system_actions` - removed experimental feature to flush your cache from the about screen
+- `system_actions` - removed experimental feature to flush app cache from the about screen
 
 ### BC BREAKS
 
@@ -41,8 +35,6 @@ Thanks to the new structure, you should be able to remove almost everything from
 
 ## [0.9](https://github.com/kevinpapst/kimai2/releases/tag/0.9)
 
-Follow the normal update and database migration process (see above).
-
 Remember to execute the necessary timezone conversion script, if you haven't updated to 0.8 before (see below)!
 
 ### BC BREAKS