- Database namespace is now NadekoBot.Db

- Db related code is now in src/NadekoBot/Db
- Finished major part of the db refactor, but many optimizations are left to be made

src/NadekoBot/Db/Extensions/CurrencyTransactionExtensions.cs

@@ -0,0 +1,21 @@
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.EntityFrameworkCore;
+using NadekoBot.Core.Services.Database.Models;
+
+namespace NadekoBot.Db
+{
+    public static class CurrencyTransactionExtensions
+    {
+        public static List<CurrencyTransaction> GetPageFor(this DbSet<CurrencyTransaction> set, ulong userId, int page)
+        {
+            return set.AsQueryable()
+                .AsNoTracking()
+                .Where(x => x.UserId == userId)
+                .OrderByDescending(x => x.DateAdded)
+                .Skip(15 * page)
+                .Take(15)
+                .ToList();
+        }
+    }
+}