Refactor mysql and postgresql apps

Create base class 'io.murano.database.Sql'  for mysql and postgresql apps.
Change their design and implementation.
Make Tomcat app work on Ububtu
Make Apache Server app work on Ubuntu
Update Sql apps
Update Apache Server
Add Zabbix apps
Add Wordpress app
Update Tomcat app
Merge pull request #28 from ddovbii/master

Refactor sql apps