refactoring: Issue-1694: Improve caching pattern code quality (#1810)

* Changed database implementation. Removed static objects.

* Fix Logs

* Fix 40 errors from checkstyle plugin run. 139 left))

* Fix CacheStore errors from checkstyle plugin 107 left

* Fix last errors in checkstyle.

* Fix sonar issues

* Fix issues in VALIDATE phase

* Fix Bug with mongo connection. Used "Try with resources"

* Add test

* Added docker-compose for mongo db. MongoDb db work fixed.

* Provided missing tests

* Comments to start Application with mongo.

* Fixes according PR comments. Mainly Readme edits.

* Remove duplicated imports

caching/docker-compose.yml

@@ -0,0 +1,11 @@
+version: '3.7'
+services:
+  mongodb_container:
+    image: mongo:latest
+    environment:
+      MONGO_INITDB_ROOT_USERNAME: root
+      MONGO_INITDB_ROOT_PASSWORD: rootpassword
+    ports:
+      - 27017:27017
+    volumes:
+      - ./mongo-data/:/data/db