added docker dev environment and fixed some bugs

docker-compose.yml

@@ -0,0 +1,19 @@
+version: '3'
+services:
+  web:
+    image: jeanblanchard/tomcat:7
+    ports:
+    - "8080:8080"
+  db:
+    image: mariadb
+    restart: always
+    environment:
+      MYSQL_ROOT_PASSWORD: "password"
+      MYSQL_DATABASE: "zallery"
+      MYSQL_USER: "zallery"
+      MYSQL_PASSWORD: "password"
+  db_admin:
+    image: adminer
+    restart: always
+    ports:
+    - 8081:8080