shorten credits with K/M suffixes

Journal/Credits.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace NonaBGS.Journal {
+    public class Credits {
+        public static string FormatCredits(int amount) {
+            if ((amount % 1000000) == 0) {
+                amount /= 1000000;
+                return string.Format("{0}M CR", amount);
+            } else if ((amount % 1000) == 0) {
+                amount /= 1000;
+                return string.Format("{0}K CR", amount);
+            }
+
+            return string.Format("{0} CR", amount);
+        }
+    }
+}

Journal/MissionCompletedEntry.cs

@@ -101,7 +101,7 @@ namespace NonaBGS.Journal {
             }
 
             if (donated > 0) {
-                builder.AppendFormat(" ({0} CR)", donated);
+                builder.AppendFormat(" ({0})", Credits.FormatCredits(donated));
             }
 
             readable_name = builder.ToString().Trim();