Make CHANGES into a pretty markdown (mhammond#2621)

Author: Avasam

AutoDuck/pywin32-document.xml

@@ -1,6 +1,6 @@
 <document>
     <important>
-        <item name="View the change log" href="html/CHANGES.txt"/>
+        <item name="View the change log" href="html/CHANGES.md"/>
     </important>
     <links>
         <item name="Python Web Site" href="https://www.python.org"/>

AutoDuck/pywin32.mak

@@ -30,7 +30,7 @@ HTML_FILES = $(WIN32_HELP_DIR)\*.html \
 		$(WIN32COMEXT_DIR)/axscript/demos/client/ie/* \
 		$(ISAPI_DIR)/doc/*.html \
 		$(PYTHONWIN_DIR)/readme.html $(PYTHONWIN_DIR)/doc/* $(PYTHONWIN_DIR)/doc/debugger/* \
-		../CHANGES.txt \
+		../CHANGES.md \
 
 
 WIN32_SOURCE = $(WIN32_SOURCE_DIR)/*.cpp \