Add changelog

CHANGES.txt

+version 0.6 Nicolas Delaby
+==========================
+Bug Fix
+-------
+* Fix generated xpath expression, the root element was missing.
+
+
+version 0.5 Nicolas Delaby
+==========================
+Features
+--------
+
+* Add support of namespaces
+* Support xupdate:insert-after
+
+version 0.4 Nicolas Delaby
+==========================
+Features
+--------
+* Change output of xupdate:append by adding Implied attribute child
+
+
+version 0.3 Nicolas Delaby
+==========================
+Bug Fix
+-------
+* Append position in xpath expression when value of id attribute is not unique regarding is sibling
+
+
+version 0.2 Nicolas Delaby
+==========================
+Bug Fix
+-------
+* Position in xpath starts from 1
+
+
+version 0.1 Tatuya Kamada
+=========================
+Features
+--------
+* ERP5diff implemented with ElemenTree (lxml)
+
+
+version 0 Yoshinori Okuji
+=========================
+
+* initial ERP5diff with DOM API (minidom)