Change Get-MediaRenderers, HtmlEncoding to HwID

Changing Get-MediaRenderers to list all "UMB\*" devices which should
contain all available DLNA devices, plus a few extra redundant stuff,
but better more than less right? Users should be able to easily
distinguish their devices from the list.

Adding a missing HtmlEncode to the hardware id for the PackageInfo.xml
file. My AVR had a '&' in it's name which required HtmlEncoding. Worked
like a charm after I added it :)
Fixing Get-MediaRenderers again.

Changing the search parameters as per suggestion from Rafael.
Merge pull request #1 from stebet/master

Adjust Media Renderer search criteria, fix metadata bug