Changed build script to exclude the Demo package because it is not for consumption via NuGet.
Changed build script to exclude the Demo package because it is not for consumption via NuGet.

apache/lucenenet,apache/lucenenet,sisve/lucenenet,NightOwl888/lucenenet,laimis/lucenenet,apache/lucenenet,sisve/lucenenet,NightOwl888/lucenenet,apache/lucenenet,jeme/lucenenet,jeme/lucenenet,jeme/lucenenet,jeme/lucenenet,laimis/lucenenet,NightOwl888/lucenenet,NightOwl888/lucenenet