refactor!(server): drop Cassandra support

Author: syncush

src/configManager/models/database/databaseConnector.js

@@ -1,7 +1,5 @@
 'use strict';
-const sequelizeConnector = require('./sequelize/sequelizeConnector');
-
-const databaseConnector = sequelizeConnector;
+const databaseConnector = require('./sequelize/sequelizeConnector');
 
 module.exports = {
     init,

src/database/database.js

@@ -1,7 +1,6 @@
 'use strict';
 
-let sequelizeConnector = require('./sequlize-handler/sequlize');
-let databaseConnector = sequelizeConnector;
+const databaseConnector = require('./sequlize-handler/sequlize');
 
 module.exports.init = () => {
     return databaseConnector.init();