Update README.md

Author: ajnebro

README.md

@@ -120,8 +120,8 @@ The current release of jMetalPy (v1.8.0) contains the following components:
 ## Changelog
 
 * [Current]
-  * Refactor class BinarySolution to use numpy arrays
-  * Refactor class Solution
+  * Refactor algorithm SPEA2 
+  * Refactor class Solution, BinarySolution, and FloatSolution
   * Added Unimodal Normal Distribution Crossover (UNDX), BLX-Alpha, BLX-Alpha-Beta and Arithmetic crossover operators.
   * Added Levy flight and power-law mutation operators.
 * [v.1.8.0]