Quick command implementation (#472)

* Separating "SSH Info" and "Quick Launch", and updating translations.

* Adding "Quick Launch" to menu.

* Auto-complete, initial version.

* Builds, but not finished.

* Improved, but there are still some bugs...

* Minor changes.

* Refactroing request/response identifiers.

* Improving command history.

* Minor refactoring.

* Deleting history by using "Del" key.

* Handling mosh special case in quick commands.

* SSH command handled as any other command in the path.

* New resource strings.

* Fixing quick command links.

* Fixing after-merging bugs.

* Improving filtering.

* Finishing filtering.

* Changing placeholder text.

* Minor refactoring.

* Updating resources.

* Renaming NewRemoteTab back to NewSshTab.

FluentTerminal.Models/Requests/CheckFileExistsRequest.cs

@@ -2,9 +2,7 @@
 {
     public class CheckFileExistsRequest : IMessage
     {
-        public const byte Identifier = 12;
-
-        byte IMessage.Identifier => Identifier;
+        public byte Identifier => (byte) MessageIdentifiers.CheckFileExistsRequest;
 
         public string Path { get; set; }
     }