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/tso.common/Utils/Cache/CacheKey.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace FSO.Common.Utils.Cache
+{
+    public class CacheKey : IEqualityComparer<CacheKey>, IEquatable<CacheKey>
+    {
+        public static CacheKey Root = CacheKey.For();
+
+        public string[] Components { get; internal set; }
+
+        protected CacheKey(string[] components)
+        {
+            this.Components = components;
+        }
+
+        public override int GetHashCode()
+        {
+            return GetHashCode(this);
+        }
+
+        public bool Equals(CacheKey x, CacheKey y)
+        {
+            return x.Components.SequenceEqual(y.Components);
+        }
+
+        public bool Equals(CacheKey other)
+        {
+            return Equals(this, other);
+        }
+
+        public int GetHashCode(CacheKey obj)
+        {
+            int hashcode = 0;
+            foreach (string value in obj.Components)
+            {
+                if (value != null)
+                    hashcode += value.GetHashCode();
+            }
+            return hashcode;
+        }
+
+        public static CacheKey For(params object[] components)
+        {
+            return new CacheKey(components.Select(x => "" + x).ToArray());
+        }
+
+        public static CacheKey Combine(CacheKey domain, params object[] components)
+        {
+            var newComponents = new string[domain.Components.Length+components.Length];
+            Array.Copy(domain.Components, newComponents, domain.Components.Length);
+            Array.Copy(components.Select(x => "" + x).ToArray(), 0, newComponents, domain.Components.Length, components.Length);
+            return new CacheKey(newComponents);
+        }
+
+    }
+}