fix bug 22086, by storing map data correctly in savegame summaries

The bug was that minimap previews for save games were not appearing,
or that the wrong ones were appearing.

It seems that because of more relics from this commit / related,

https://github.com/wesnoth/wesnoth/commit/c17d84b12

the savegame summaries generated by "extract savegame summary" were
bugged and didn't store the map data correctly. This bug wasn't
obvious because the save game load dialog tries to scavenge what
ever the current game config is for map data if it can't find this,
but all of the saveindex data was being generated incorrectly.

After this commit all the save files seem to work correctly,
except for start-of-scenario saves for reasons that aren't clear
to me, and which I think is a separate issue. (In that case,
something is going wrong with the game_config lookup process most
likely.)

This only appears to fix the bug for normal saves, autosaves, and
replay saves.
update changelogs
fixup e7eb08d0cd2d57b55bf084b669fbeec8d283db33

I'm not sure how the '=' became a comma, I could have sworn I
typed '='. Also strange that it compiled, and that the commit
appeared to help the bug...
add some additional remarks about the save_index
Fix SCATTER_UNITS placing units on map borders
Updated changelog
[filter_vision] tag should return true if *any* viewer matches

This commit also fixes a bug where filter_vision was different
in a unit filter vs a location filter with regards to what happens
when different numbers of matches are found.
add [has_ally],[has_enemy] tags for standard side filter

Unlike [allied_with] and [enemy_of], these will match if only if
there is *any* ally or enemy matching the filter. The other versions
of the tag match only if all sides matching the filter are
allied / opposed.
Merge branch 'fixup_filter_vision' into 1.12
update changelogs
Merge branch 'add_has_ally/enemy' into 1.12
update changelogs
updated French translation
updated Vietnamese translation
pot-update and regenerated doc files

preparing for 1.11.16
no new/changed strings
fixed Vietnamese manpages
reran pot-update after Vietnamese manpages fixes

* recreated Chinese (Simplified and Traditional) as well as Vietnamese
  manpages
* no new/changed strings
bump version to 1.11.16
post release version bump to 1.11.16+dev
Fixed map/scenario generation for networked MP campaigns.

The genaration code was inserted before host enters MP Connect mode so that
non-host players would receive an up-to-date level config. This approach
introduces some code duplication, but a better approach would require too much
refactoring and so it doesn't seem suitable for 1.12.

This fixes bug #22307.

N.B. fix follows this suggestion: https://gna.org/bugs/index.php?22307#comment1