Removed NioTSO client and server

- NioTSO client isn't needed because we're using RayLib
- Added FreeSO's API server to handle most backend operations

server/FSO.Server.Database/DA/Hosts/IHosts.cs

@@ -0,0 +1,12 @@
+using System.Collections.Generic;
+
+namespace FSO.Server.Database.DA.Hosts
+{
+    public interface IHosts
+    {
+        IEnumerable<DbHost> All();
+        DbHost Get(string call_sign);
+        void CreateHost(DbHost host);
+        void SetStatus(string call_sign, DbHostStatus status);
+    }
+}