feat: add upgrade doc

Author: Yozhef

UPGRADE-1.0.md

@@ -0,0 +1,83 @@
+Upgrade Symfony Health Check Bundle V1.0.0
+=================================
+
+Step 1: Update the Symfony Health Check Bundle via Composer
+----------------------------------
+```console
+$ "macpaw/symfony-health-check-bundle": "^v1.0.0"
+```
+
+### Next, use Composer to download new versions of the libraries:
+```console
+$ composer update "macpaw/symfony-health-check-bundle"
+```
+
+###Dependency Errors
+
+If you get a dependency error, it may mean that you also need to upgrade other libraries that are dependencies of the libraries. To allow that, pass the --with-all-dependencies flag:
+```console
+$ composer update "macpaw/symfony-health-check-bundle" -with-all-dependencies
+```
+
+Step 2: Update the Symfony Health Check Bundle via Composer
+----------------------------------
+
+##Automatical:
+Over time - and especially when you upgrade to a new version of a library - an updated version of the recipe may be available. These updates are usually minor - e.g. new comments in a configuration file - but it's a good idea to keep your files in sync with the recipes.
+
+Symfony Flex provides several commands to help upgrade your recipes. Be sure to commit any unrelated changes you're working on before starting:
+
+```console
+$ composer recipes
+
+
+$ composer recipes symfony/framework-bundle
+
+
+$ composer recipes:install symfony/framework-bundle --force -v
+```
+
+The tricky part of this process is that the recipe "update" does not perform any intelligent "upgrading" of your code. Instead, the updates process re-installs the latest version of the recipe which means that your custom code will be overridden completely. After updating a recipe, you need to carefully choose which changes you want, and undo the rest.
+
+##Manual:
+
+### Old Config:
+`config/packages/symfony_health_check.yaml`
+```yaml
+symfony_health_check:
+    health_checks:
+        - id: symfony_health_check.doctrine_check
+```
+
+### New Config:
+```yaml
+symfony_health_check:
+    health_checks:
+        - id: symfony_health_check.doctrine_check
+    ping_checks:
+        - id: symfony_health_check.status_up_check
+```
+
+Security Optional:
+----------------------------------
+`config/packages/security.yaml`
+
+### Old Config:
+```yaml
+    firewalls:
+        healthcheck:
+            pattern: ^/health
+            security: false
+```
+
+### New Config:
+```yaml
+    firewalls:
+        healthcheck:
+            pattern: ^/health
+            security: false
+        ping:
+            pattern: ^/ping
+            security: false
+```
+