I18N: Update po files

I18N: Update po files

The old translations where build together in the C code. Now we pass the
complete string to gettext. Update the po files and combine the old
translations into new ones.

In the old version the strings translated where

    "[-- This %s/%s attachment "

    "(size %s bytes) "

    "has been deleted --]\n"

    "[-- on %s --]\n"

The four new strings are

    "[-- This %s/%s attachment (size %s bytes) has been deleted --]\n"
    "[-- on %s --]\n"

    "[-- This %s/%s attachment (size %s bytes) has been deleted --]\n"

    "[-- This %s/%s attachment has been deleted --]\n
    "[-- on %4$s --]\n"

    "[-- This %s/%s attachment has been deleted --]\n"