Zabbix

..F....... [ZBXNEXT-4588] improvements:

CWidgetFieldGraphDataSet.php
 - the validation has been moved into validation rules from "validate()" method
 - methods "getFieldLayout()", "getJavascript()" and "getTemplate()" should be moved to more proper place - "CWidgetHelper()"

CControllerWidgetSvgGraphView.php
 - fixed validation for input parameters