Fix encodinganalog in EAD export, fixes #4505

Squashed commit of the following:

commit ed15c9fef872c5753ecdd4dc45e3833871e5ec17
Author: José Raddaoui Marín <raddaouimarin@gmail.com>
Date:   Wed May 15 16:44:35 2013 +0200

    Fix arch notes EAD import

commit 9a6d260aec1761f16f947d5f5f159f69e87c9c64
Author: José Raddaoui Marín <raddaouimarin@gmail.com>
Date:   Wed May 15 16:43:44 2013 +0200

    Check encodinganalog where the value can be empty

commit 6a549046f37eebb07f6ff3834a0febffe33c57de
Author: José Raddaoui Marín <raddaouimarin@gmail.com>
Date:   Wed May 15 16:34:15 2013 +0200

    Add four RAD values

commit cec67ba60c78bb77f53e7e2ef3477a6feaffe4e0
Merge: dd3a4e3 11df6e6
Author: José Raddaoui Marín <raddaouimarin@gmail.com>
Date:   Wed May 15 15:26:59 2013 +0200

    Fix conflicts

commit dd3a4e3681f408945c46b8da3279a9769a5adfca
Author: José Raddaoui Marín <raddaouimarin@gmail.com>
Date:   Wed Apr 24 07:42:07 2013 +0200

    Change the encodinganalog attributes value in EAD.

    Use RAD's standard or ISAD's standard for encodinganalog values
    in EAD export depending on the information object template selected

commit 498ee47b5b9439f1c484f696c7001e9dbb04a53b
Author: José Raddaoui Marín <raddaouimarin@gmail.com>
Date:   Wed Apr 24 04:12:56 2013 +0200

    Fix number error and cosmetic changes