Correct the installation and removal of plugins

Upgrading plugins was broken for various reasons. There are four
fixes and a minor one:

1. Use a directory name based only on the `Name` of the plugin, not
   the source filename, which contains the version. Avoids strange
   duplication of the plugin.
2. Use the new directory name for the deletes if it's present, so
   that installation and removal happen at that directory level
   and we don't leave empty folders laying around. Ensures we
   properly remove additional resources in plugins too, not just
   the main `.dll` file.
3. Ignore the incoming `target` when installing, and always set
   it ourself to the proper directory, which would matter when
   reinstalling.
4. Deletes an existing target directory before installing if it
   exists. Note that not calling any of the plugin removal code
   is intentional; I suspect that would delete configurations
   unexpectedly when upgrading which would be annoying. This way,
   it just replaces the files and then reloads.
5. (Minor) Added some actual debug messages around the plugin
   download section so failures can be more accurately seen.

1 files changed, 1 insertions, 1 deletions

diff --git a/Emby.Server.Implementations/ApplicationHost.cs b/Emby.Server.Implementations/ApplicationHost.cs
index dbdf246a2..05f8a8a5e 100644
--- a/Emby.Server.Implementations/ApplicationHost.cs
+++ b/Emby.Server.Implementations/ApplicationHost.cs
@@ -1046,7 +1046,7 @@ namespace Emby.Server.Implementations
 
         private async void PluginInstalled(object sender, GenericEventArgs<PackageVersionInfo> args)
         {
-            string dir = Path.Combine(ApplicationPaths.PluginsPath, Path.GetFileNameWithoutExtension(args.Argument.targetFilename));
+            string dir = Path.Combine(ApplicationPaths.PluginsPath, args.Argument.name);
             var types = Directory.EnumerateFiles(dir, "*.dll", SearchOption.AllDirectories)
                         .Select(x => Assembly.LoadFrom(x))
                         .SelectMany(x => x.ExportedTypes)