The newlines serve the goal of keeping textlengths reasonably short in
text only mails.

This change was done by reverting the files back to the current master.

As discussed in https://github.com/splitbrain/dokuwiki/pull/2462#issuecomment-413786942

This applies a lot of formatting fixes on the language files:

1. In EOF - trimmed all empty lines except one
2. After the title - one empty line strictly
3. Corrected links to national versions of documents in dokuwiki.org if
   they exits - 4example [[doku>namespaces]] to [[doku>ar:namespaces]]
4. Corrected some over-auto-translated links to "playground:playground"
   and "wiki:syntax"
5. Torn lines are collected in one in a large number of places (except
   for RTL languages)
6. Removed e-mail signatures that now is missing in the English set of
   files

Done:
Cleanup of the mail text signature.
The signature is deleted from the txt files and moved in to lang.php
Mailer.class.php updated to insert the signature

Fix:
- Cleaner text
- no more "-- "  "--" "---" "----" problems.
- mailwrap.html is not needed anymore an can be deleted (?)

Changed files in all languages:
lang.php
mailtext.txt
password.txt
registermail.txt
subscr_digest.txt
subscr_list.txt
subscr_single.txt
uploadmail.txt
pwconfirm.txt
showrev.txt

delete?:
mailwrap.html

This was updated in the english translation a while ago, but was still
missing in some translations