fix changelog format

Author: zhangJP

ChangeLog

@@ -1,17 +1,17 @@
 2011-05-20: Version 1.2.0 
-	This is the first version under GPL-v2 license.
+    This is the first version under GPL-v2 license.
 
 2011-12-31: Version 1.2.1
-	Fix default font object mem leak bug.
-	
+    Fix default font object mem leak bug.
+    
 2012-12-31: Version 1.2.5
     Add context thread safe or shared support.
 
 2013-02-12: Version 2.0.0
-	Update code version 2.0.0 alpha.
+    Update code version 2.0.0 alpha.
 
 2014-07-16: Version 2.0.1
-	Fix font glyph advance_x bug.
+    Fix font glyph advance_x bug.
 
 2014-08-13:
     Fix crash bug for path clip.