[HER-1636] H3: Failed get of replay char sequence due the OutOfMemoryError: Map failed (port HER-1482)

(from nlevitt's H2 commit message:)
* InMemoryReplayCharSequence.java
    new, simple ReplayCharSequence that supports any encoding, keeping everything in memory
* GenericReplayCharSequence.java
    If the encoding supports random access, memory maps the backing file directly; otherwise decodes to UTF-16 and maps that. Supports the first Integer.MAX_VALUE bytes of the file. Maps up to 64M; moves the map around as necessary for larger files.
* Latin1ByteReplayCharSequence.java
    removed, functionality split between InMemoryReplayCharSequence and GenericReplayCharSequence
* ReplayCharSequenceTest.java
    xestHugeReplayCharSequence() - uncomment to test a huge replay char sequence
    testReplayCharSequenceByteToStringOverflow() - test both UTF-8 and windows-1252
* RecordingOutputStream.java
    use the new ReplayCharSequences

commons/src/main/java/org/archive/io/ReplayInputStream.java

@@ -1,27 +1,22 @@
-/* ReplayInputStream
+/*
+ *  This file is part of the Heritrix web crawler (crawler.archive.org).
  *
- * $Id$
+ *  Licensed to the Internet Archive (IA) by one or more individual 
+ *  contributors. 
  *
- * Created on Sep 24, 2003
+ *  The IA licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
  *
- * Copyright (C) 2003 Internet Archive.
+ *      http://www.apache.org/licenses/LICENSE-2.0
  *
- * This file is part of the Heritrix web crawler (crawler.archive.org).
- *
- * Heritrix is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Lesser Public License as published by
- * the Free Software Foundation; either version 2.1 of the License, or
- * any later version.
- *
- * Heritrix is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Lesser Public License for more details.
- *
- * You should have received a copy of the GNU Lesser Public License
- * along with Heritrix; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
  */
+
 package org.archive.io;
 
 import java.io.File;
@@ -279,4 +274,9 @@ public class ReplayInputStream extends SeekInputStream
     public long position() throws IOException {
         return position;
     }
+    
+    // package private
+    byte[] getBuffer() {
+        return buffer;
+    }
 }