Update CHANGELOG for changes imposed in 1.0.2, 1.0.3 and 1.0.4

Author: Colman Yau

CHANGELOG.rst

@@ -2,14 +2,25 @@
 CHANGELOG
 =========
 
-1.0.1 (layer_v3)
+1.0.4 (layer_v4)
+===================
+* Attempt to report profile before sample to avoid incorrect profile end time (Issue #15)
+* Add synthetic frame for lxml schema init
+
+1.0.3
+===================
+* Add requirements.txt in PyPI source release (Issue #13)
+
+1.0.2
 ===================
+* Fix timestamp bug in file reporter (Issue #10)
 
+1.0.1 (layer_v3)
+===================
 * Fix bug for running agent in Windows; Update module_path_extractor to support Windows applications
 * Use json library instead of custom encoder for profile encoding for more reliable performance
 * Specify min version for boto3 in setup.py
 
 1.0.0 (layer_v1, layer_v2)
 ==========================
-
 * Initial Release