fixed #4343: Prepare MP2 repository to use NuGet packages easily - Client, Server, ServiceMonitor
#4343: moved solution files for Tools to one common directory to share .nuget\NuGet.exe
#4342: Update CommandLine parsing library
 - using CommandLine.dll via NuGet for Client, Server & ServiceMonitor
 - removed CommandLine code from MediaPortal.Utilities
#4342: using CommandLine.dll via NuGet for MergeMSI & TransifexHelper