Host filter is always a regular expression?

[Marcel Arentz]

Using a regex in Host filter seems to be not optional and not working at all.
Steps to reproduce:

• Add a Panel and select combined graphs
• Activate regex for Host filter and add the beginning of a host name that matches to at least two hosts (e.g. myHost for 'myHost1' and 'myHost2')
• configure the rest of the stuff and save the Panel - it should work as expected
• Go back to the panel, deactivate regex and select the host directly
• The Panel still shows the metrics for the regular expression.

If you reproduce the steps by not adding a regular expression first, you will not be able to select any graph to show. -> The selection is simply not used.