WIP: #5456 added support for MySQL8 to installer
resolution:
- added mysql_info class to obtain RDBMS engine (maria and mysql support only, no percona) and version
- handled password validation moved from plugins to components in mysql8
- fixed output of unwanted plugins
- extended rights assignment to ispconfig db user (added global access to admin variables)
- removed new line after ?>, converted spaces to tabs, truncated whitespaces from line endings (IDE feature)