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/DirectionUtils.cs

@@ -0,0 +1,75 @@
+using Microsoft.Xna.Framework;
+using System;
+
+namespace FSO.Common.Utils
+{
+    public static class DirectionUtils
+    {
+
+        /// <summary>
+        /// Finds the difference between two radian directions.
+        /// </summary>
+        /// <param name="a">The direction to subtract from.</param>
+        /// <param name="b">The direction to subtract.</param>
+        public static double Difference(double a, double b) {
+            double value = PosMod(b-a, Math.PI*2);
+            if (value > Math.PI) value -= Math.PI * 2;
+            return value;
+        }
+
+        /// <summary>
+        /// Normalizes a direction to the range -PI through PI.
+        /// </summary>
+        /// <param name="dir">The direction to normalize.</param>
+        public static double Normalize(double dir)
+        {
+            dir = PosMod(dir, Math.PI * 2);
+            if (dir > Math.PI) dir -= Math.PI * 2;
+            return dir;
+        }
+
+        /// <summary>
+        /// Normalizes a direction in degrees to the range -180 through 180.
+        /// </summary>
+        /// <param name="dir">The direction to normalize.</param>
+        public static double NormalizeDegrees(double dir)
+        {
+            dir = PosMod(dir, 360);
+            if (dir > 180) dir -= 360;
+            return dir;
+        }
+
+        /// <summary>
+        /// Calculates the mathematical modulus of a value.
+        /// </summary>
+        /// <param name="x">The number to mod.</param>
+        /// <param name="x">The factor to use.</param>
+        public static double PosMod(double x, double m)
+        {
+            return (x % m + m) % m;
+        }
+
+        private static int[] tab32 = new int[] {
+             0,  9,  1, 10, 13, 21,  2, 29,
+            11, 14, 16, 18, 22, 25,  3, 30,
+             8, 12, 20, 28, 15, 17, 24,  7,
+            19, 27, 23,  6, 26,  5,  4, 31
+        };
+
+        public static int Log2Int(uint value)
+        {
+            value |= value >> 1;
+            value |= value >> 2;
+            value |= value >> 4;
+            value |= value >> 8;
+            value |= value >> 16;
+            return tab32[(uint)(value * 0x07C4ACDD) >> 27];
+        }
+
+        public static float QuaternionDistance(Quaternion q1, Quaternion q2)
+        {
+            var inner = q1.X * q2.X + q1.Y * q2.Y + q1.Z * q2.Z + q1.W * q2.W;
+            return (float)Math.Acos(2 * (inner * inner) - 1);
+        }
+    }
+}