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

- jQuery to 3.1.1
- jQuery UI to 1.12.1
- jQuery Migrate to 3.0.0

There are a few warnigs from migrate that have to be fixed. The toggles
in the Media Manager are also missing their proper icons.

This now pulls all data from official jQuery sources. Either their CDN
or their github account. Google tends to serve outdated or even broken
files :-(

Unfortunately there's no simple way to get the latest stable jQuery-UI
so for now the version has to be adjusted manually in the script.

Attention: $lang['register'] has been renamed to $lang['btn_register'],
anyone using that in any plugin or template should adjust it.