Add ``short_name`` to all tiles.

Use this as title in the tile list.  This can be translated.
Rebuild i18n.
Dutch translations.
Update manual.pot.

Some tiles were removed, some added.
This contains msgids from zcml files, which i18ndude does not yet extract unfortunately.
Rebuild i18n.
Dutch
Merge pull request #336 from collective/maurits-translate-tilelist

Translate the tile list