update change log for 1.4

Author: xwings

ChangeLog

@@ -1,5 +1,14 @@
 This file details the changelog of Qiling Framework.
 
+------------------------------------
+[Version 1.4]: Oct 20th, 2021
+- Added MCU Engine
+- Bug fix for qdb
+- Bug fix for debugger
+- Bug fix for ql.mem
+- Bump to Unicorn 2
+
+
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 [Version 1.3]: Sept 25th, 2021