Hook up new native crypt code (disabled uses pure Java version of DES)

Author: enebo

core/src/main/java/org/jruby/RubyString.java

@@ -2653,13 +2653,13 @@ public IRubyObject prepend(ThreadContext context, IRubyObject other) {
     @JRubyMethod(name = "crypt")
     public RubyString crypt(ThreadContext context, IRubyObject other) {
         RubyString otherStr = other.convertToString();
-        ByteList salt = otherStr.getByteList();
-        if (salt.getRealSize() < 2) {
+        String salt = otherStr.asJavaString();
+        if (salt.length() < 2) {
             throw context.runtime.newArgumentError("salt too short(need >=2 bytes)");
         }
 
-        salt = salt.makeShared(0, 2);
-        RubyString result = RubyString.newStringShared(context.runtime, JavaCrypt.crypt(salt, this.getByteList()));
+        RubyString result = RubyString.newString(context.runtime,
+                context.runtime.getPosix().crypt(salt, asJavaString()).toString());
         result.infectBy(this);
         result.infectBy(otherStr);
         return result;