Migrated the project to dotnet core 3.0

src/NotifyIconWpf/Interop/NotifyIconVersion.cs

@@ -0,0 +1,27 @@
+namespace Hardcodet.Wpf.TaskbarNotification.Interop
+{
+    /// <summary>
+    /// The notify icon version that is used. The higher
+    /// the version, the more capabilities are available.
+    /// </summary>
+    public enum NotifyIconVersion
+    {
+        /// <summary>
+        /// Default behavior (legacy Win95). Expects
+        /// a <see cref="NotifyIconData"/> size of 488.
+        /// </summary>
+        Win95 = 0x0,
+
+        /// <summary>
+        /// Behavior representing Win2000 an higher. Expects
+        /// a <see cref="NotifyIconData"/> size of 504.
+        /// </summary>
+        Win2000 = 0x3,
+
+        /// <summary>
+        /// Extended tooltip support, which is available for Vista and later.
+        /// Detailed information about what the different versions do, can be found <a href="https://docs.microsoft.com/en-us/windows/win32/api/shellapi/nf-shellapi-shell_notifyicona">here</a>
+        /// </summary>
+        Vista = 0x4
+    }
+}