[1/40] Work on C4::Labels::Layout module and tests

[1/40] Work on C4::Labels::Layout module and tests

NOTE: This patch is the first of 40 which almost completely re-factor the
label creator code into a hopefully more scalable form. The new format is
a move in direction of OO handling labels, batches, templates, layouts, and
profiles as objects thus permitting easier implementation of features and
enhancements. It should be possible to export label data in any format one
might choose with the simple addition of a script similar to those included
which produce pdf, csv, and xml format.

One of the larger improvements is a change in workflow that results in template,
layout, and start label selection occurring just before export.

There are also various bugfixes and smaller interface improvements woven into it.

It should be noted that this patch series removes the patron card creator feature
for the present. This feature was only partially completed. A completed variation
will be submitted as a separate patch series to follow in the near future.

The following bugs and enhancements are fixed by this series of patches:

2944 Search to add items to a label batch broken
2061 labels_conf DB values: NULL vs. 0
2511 CSV format string is not cleared when unselected in the label layout editor
2515 Re-factor C4::Labels::DrawSpineText
2823 Label Generator not generating barcodes
3171 Problem due to internationalization in label-create-template.tmpl in de-DE and possibly others
3180 Active settings for label settings should be set at print time only

This work was sponsored by Foundations Bible College & Seminary, Dunn, NC USA