migrate to v4

public/v4/apps/mysql.yml

@@ -0,0 +1,34 @@
+captainVersion: 4
+services:
+  $$cap_appname-db:
+    image: mysql:$$cap_mysql_version
+    volumes:
+      - $$cap_appname-db-data:/var/lib/mysql
+    restart: always
+    environment:
+      MYSQL_ROOT_PASSWORD: $$cap_db_pass
+    caproverExtra:
+      notExposeAsWebApp: "true"
+caproverOneClickApp:
+  variables:
+    - id: $$cap_mysql_version
+      label: MySQL Version
+      defaultValue: "5.7"
+      description: Check out their Docker page for the valid tags https://hub.docker.com/r/library/mysql/tags/
+      validRegex: /^([^\s^\/])+$/
+    - id: $$cap_db_pass
+      label: MySQL Root password
+      description: ""
+      validRegex: /.{1,}/
+  instructions:
+    start: >-
+      MySQL is the world's most popular open source database. With its proven performance, reliability and ease-of-use, MySQL has become the leading database choice for web-based applications, covering the entire range from personal projects and websites, via e-commerce and information services, all the way to high profile web properties including Facebook, Twitter, YouTube, Yahoo! and many more.
+
+       After installation on CapRover, it will be available as srv-captain--YOUR_CONTAINER_NAME at port 3306 to other CapRover apps.
+
+      Enter your MySQL Configuration parameters and click on next. It will take about a minute for the process to finish.
+    end: "MySQL is deployed and available as srv-captain--$$cap_appname-db:3306 to other apps. For example with NodeJS, you do 'var con = mysql.createConnection({ host: 'srv-captain--$$cap_appname-db', user: 'root', password: '*********' });'"
+  displayName: MySQL
+  isOfficial: true
+  description: MySQL is a relational database management system based on SQL
+  documentation: Taken from https://docs.docker.com/compose/mysql/ port mapping removed from WP as it's not needed