some minor bugs and typos

[Stavros]

Hi there.
Sometimes when I delete all channels from the device, the channel groups still remain, how do I delete all the groups?
Also, there is a typo when deleting all the channels, it says "are you sure you want to delete all channel from the device?" it should say "are you sure you want to delete all channels from the device?"
Cheers.

[mvallevand]

It is not automatic for those that want to keep them

Go to Setting->Channels->Advanced Tools->Channel Groups and there is a trash can for deletion.

Perhaps your screen reader can read the wiki https://github.com/sub3/NextPVR/wiki/Add...t-channels

Martin