Item filter related issues

There are several issues in the item filter and sub-filter:

1. No way to change "Data type". Is it always "all".
2. When selecting a host in the filter, host group selection must be taken into account.
3. When selecting an application in the filter, host selection must be taken into account.
4. Change of any drop down in the filter should lead to automatic page refresh, as with Type of Information, Type and other fields.