Update Changelog

Changelog.txt

@@ -1,6 +1,18 @@
 August 2024
+  * New Features
+    * Implement a consistent (and purple!) UI theme (#5865)
+    * Added Perf-Info button to Dump a system to systemeditor compatible JSON (#5888)
+
   * Fixes
     * Fix crash in mission list in hyper space when combat mission (#5872)
+    * Invert illegal commodities icons in the Economy & Trade view (#5884)
+    * Police patrol improvement, don't confuse player with pirate (#5809)
+    * Fix intro screen ship spinner parade's lack of randomness for some (#5896)
+
+  * Internal Changes
+    * Separating shield.models (#5853)
+    * Separate shield meshes from ship models (#5840)
+    * Don't build against lzcnt by default and enable USE_SSE42 only on Intel (#5871)
 
 July 2024
   * New Features