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/LotVisits/LotVisitUtils.cs

@@ -0,0 +1,50 @@
+using System;
+
+namespace FSO.Server.Database.DA.LotVisits
+{
+    public static class LotVisitUtils
+    {
+        /// <summary>
+        /// Calculates the overlap between two date ranges.
+        /// Useful utility function for calculating visit hours.
+        /// </summary>
+        /// <param name="day"></param>
+        /// <param name="start"></param>
+        /// <param name="end"></param>
+        public static TimeSpan CalculateDateOverlap(DateTime r1_start, DateTime r1_end, DateTime r2_start, DateTime r2_end)
+        {
+            var startsInRange = r2_start >= r1_start && r2_start <= r1_end;
+            var endsInRange = r2_end <= r1_end && r2_end >= r1_start;
+
+            if (startsInRange && endsInRange)
+            {
+                //Within the range / equal
+                return r2_end.Subtract(r2_start);
+            }
+            else if (startsInRange)
+            {
+                //Starts within range but does not end in range
+                return r1_end.Subtract(r2_start);
+            }
+            else if (endsInRange)
+            {
+                //Ends in range but does not start in range
+                return r2_end.Subtract(r1_start);
+            }
+            else
+            {
+                return new TimeSpan(0);
+            }
+        }
+
+        /// <summary>
+        /// Returns midnight of the current day.
+        /// Useful utility function for calculating visit hours.
+        /// </summary>
+        public static DateTime Midnight()
+        {
+            var now = DateTime.UtcNow;
+            return new DateTime(now.Year, now.Month, now.Day, 0, 0, 0);
+        }
+    }
+}