typo + readme update

README.md

@@ -13,6 +13,9 @@ file: `fermat-prime-test.hs`
 ### Miller Rabin's prime test
 file: `miller-rabin-prime-test.hs`
 
+### Solovey Strassen's prime test
+file: `SoloveyStrassen.hs`
+
 ## factorization algorithms
 
 ### Fermat's factorization