[pvr] properly update the view mode when switching channels
Rename isDVDImage() to isDiscImage().

Conflicts:
	xbmc/video/windows/GUIWindowVideoBase.cpp
[win32] rename and generalise packaging folders. also simplify NSIS installer to match package folders
Merge pull request #5067 from Jalle19/fix-channel-view-mode

[pvr] properly update the view mode when switching channels