Make SeekableByteArayChannelImpl public

Author: headius

core/src/main/java/org/jruby/util/io/SeekableByteChannelImpl.java

@@ -24,7 +24,7 @@
  * Seekable byte channel impl over a byte array stream.
  * @author kares
  */
-final class SeekableByteChannelImpl extends AbstractInterruptibleChannel
+public final class SeekableByteChannelImpl extends AbstractInterruptibleChannel
     implements ReadableByteChannel, SeekableByteChannel {
 
     private final ByteArrayInputStream in;