Database Improvements

Brought in all the myriad improvements to the database tools from the Stream Pixels project
Added configurable nested entry grouping

Assets/Scripts/ServerShared/CultCache/CollectionExtensions.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Security.Cryptography;
+
+public static class CollectionExtensions
+{
+    // https://stackoverflow.com/a/800469
+    public static string GetHashSHA1(this byte[] data)
+    {
+        using (var sha1 = new System.Security.Cryptography.SHA1CryptoServiceProvider())
+        {
+            return string.Concat(sha1.ComputeHash(data).Select(x => x.ToString("X2")));
+        }
+    }
+
+    // https://stackoverflow.com/a/3188835
+    public static T MaxBy<T, U>(this IEnumerable<T> items, Func<T, U> selector)
+    {
+        if (!items.Any())
+        {
+            throw new InvalidOperationException("Empty input sequence");
+        }
+
+        var comparer = Comparer<U>.Default;
+        T   maxItem  = items.First();
+        U   maxValue = selector(maxItem);
+
+        foreach (T item in items.Skip(1))
+        {
+            // Get the value of the item and compare it to the current max.
+            U value = selector(item);
+            if (comparer.Compare(value, maxValue) > 0)
+            {
+                maxValue = value;
+                maxItem  = item;
+            }
+        }
+
+        return maxItem;
+    }
+    
+    public static T MinBy<T, U>(this IEnumerable<T> items, Func<T, U> selector)
+    {
+        if (!items.Any())
+        {
+            throw new InvalidOperationException("Empty input sequence");
+        }
+
+        var comparer = Comparer<U>.Default;
+        T   maxItem  = items.First();
+        U   maxValue = selector(maxItem);
+
+        foreach (T item in items.Skip(1))
+        {
+            // Get the value of the item and compare it to the current max.
+            U value = selector(item);
+            if (comparer.Compare(value, maxValue) < 0)
+            {
+                maxValue = value;
+                maxItem  = item;
+            }
+        }
+
+        return maxItem;
+    }
+}