Imporve IoBuffer

Squashed commit of the following:

commit 5fb7b37bcee6490ea9409843c4e81b4b25ab2324
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Mon Jun 24 07:03:54 2013 +0200

    IoBuffer.compact() fix and dedicated test

commit 3462c4785a72b7dc77753ad12d76b3a27f10504e
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Mon Jun 24 01:43:54 2013 +0200

    added a few tests for IoBuffer

commit c19c4917ca6fd62efdd4d128e2d400204fc253e2
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Mon Jun 24 01:43:26 2013 +0200

    IoBuffer with some new features

commit 60d85e2dc000437c3b0d1d715cde8a5a83192d6d
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Sun Jun 23 23:16:19 2013 +0200

    It is possible to set the position to the last index + 1 on a IoBuffer (like on java.nio.Buffer)

commit fbc4085eb446795c08f2693a75cd53ab7570ee7e
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Sun Jun 23 23:08:33 2013 +0200

    IoBuffer's contains the available bytes of the ByteBuffers used for it's creation

commit 61b6b7431a637c89e3c0fda7c39ab32b9e169f21
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Sun Jun 23 23:06:11 2013 +0200

    Endianness at the IoBuffer level

commit 5348a560805c53a4c5ead81c403d0b3348fa51eb
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Sun Jun 23 23:02:40 2013 +0200

    mixed typed buffers should be handled by IoBuffers

commit 68c48c5e9b247b2e67dd551b67b8b8b113a6db81
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Sun Jun 23 22:51:22 2013 +0200

    the endianness is handled at the IoBuffer level

commit 4e3f5a5d6e0627ee876514a6d3ff6e489f9529c3
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Sun Jun 23 22:38:52 2013 +0200

    This test scenario doesn't match the array() specifications of the ByteBuffer class

commit a1c93c922d12b56459e6f8c53c2052c5805bcaf8
Author: Raphaël P. Barazzutti <raphael.barazzutti@gmail.com>
Date:   Sun Jun 23 22:30:45 2013 +0200

    when available it should return the array really backing the buffer
removed reference to xbean