#1138 Show warning for hashes that will be deprecated in 5.4

- Introduce Usage.DEPRECATED to mark the hash algorithms accordingly
- Log warning when such a deprecated hash algorithm is used
- Update hash algorithms doc page

src/main/java/fr/xephi/authme/security/crypts/Whirlpool.java

@@ -59,8 +59,12 @@ package fr.xephi.authme.security.crypts;
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+import fr.xephi.authme.security.crypts.description.Recommendation;
+import fr.xephi.authme.security.crypts.description.Usage;
+
 import java.util.Arrays;
 
+@Recommendation(Usage.DEPRECATED)
 public class Whirlpool extends UnsaltedMethod {
 
     /**