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+## Version: 0.5.0
+### Date: 2017-12-12
+1. Changed class names:
+    - `GAIndividual` -> `BinaryIndividual`
+    - `GAPopulation` -> `Population`
+    - `GASelection` -> `Selection`
+    - `GACrossover` -> `Crossover`
+    - `GAMutation` -> `Mutation`
+
+2. Added abstract Individual base class `IndividualBase`:
+    Users can inherit the `IndividualBase` class and add implementations of `encode` and `decode` methods to define you own custom individual class with different encoding methods.