update changelog

CHANGELOG

@@ -5,6 +5,17 @@
 Changelog
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+Release 2.x.x
+--------------------------------------------------------------------------------
+
+* Introduced VINA scoring function in the sidechain module. A scoring function 
+  specific RotamerConstructor is provided that comes with extensive heuristics 
+  to parametrize arbitrary compounds. 
+* Motif finding algorithm to identify objects in 3D space, e.g. binding sites.
+  The algorithm is based on principles of geometric hashing.
+* Several minor bug fixes, improvements, and speed-ups  
+
+
 Release 2.0.0
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