Split out from issue2551045(Implementing wiki move to Waldmann-EDV):

The old roundup wiki style needs to be fixed to be current with
themes from moinmoin 1.9.10. Especially compare to the modernized
style.

List of issues:
* An important box
  as configured with
http://hg.moinmo.in/moin/1.9/file/tip/docs/resetpw/wikiconfig-note-snippet.txt
is not shown with the roundup.py theme
  
as it misses to call 
http://hg.moinmo.in/moin/1.9/file/tip/MoinMoin/theme/modernized.py#l90

in header() and editorheader()

A comparision shows that some other calls are also not made,
like the following two:
{{{
# Post header custom html (not recommended)
self.emit_custom_html(self.cfg.page_header2),

# Start of page
self.startPage(),
}}}

* The icons used are a bit outfashioned as modernized as modern icons.
* A layout and icons can be improved overall like with the memodump.
https://moinmo.in/ThemeMarket/memodump

roundup-theme-fix-20190829-1.diff allows display of page_header1 notes
and thus the important notes.

Note roundup-theme-fix-20190829-1.diff has layout of usually used
page_header1 that overlaps with the search box. (This is accepted as
good enough for now, but should be fixed if more work is done on the
theme as
part of this issue.)

The theme should (in my opinion) display the date time of the last
change of the wiki page, so people can judge the age
of the information.