Silence -Wunused-parameter

It happened in open_object() if no support for opening files with xdg-open
or equivalent was enabled.
style.css,html.py: use <pre> instead of <br/>; re.sub instead of re.finditer

After looking into it some more, I think I've figured out how to handle <pre>
in the CSS. So, use that, when description has more than one line.

Also, go to re.sub for turning URLs into links. The version of Python I was
testing my code on wasn't properly handling backreferences in the replacement
string when in the form "\#", causing me to use finditer instead of sub. But
I've discovered that it does handle backreferences in the form "\g<#>". So
switch to much simpler re.sub code.
html.py: replace Windows backslashes in icon paths

This is one source of missing-image results.

There remain other reasons for missing icons. The script doesn't find images
in add-ons. And when resources are moved or renamed, they are no longer found
by the script, even if they had been found before.

Also, capitalize a sentence.
updated Hungarian translation
updated Slovak translation
SotBE S7: have scorpions target all side 1 units, not just Kapou'e

The scorpions have no concept of a side leader.  This only affects
moves toward targets, attacks were already done in this way,
Fixed recalling sometimes invalidating undo
html.py,style.css: use <pre> with no top-margin on all descriptions

After my last change dealing with this issue, I noticed that descriptions
with <pre> had an extra blank line at the top. Adding top-margin to the
CSS file made this go away, but it also made the <br/> superfluous. Thus,
it is simpler just to have every description use <pre> instead of <br/>.

This should finally resolve everything having to do with the add-on
descriptions.

If I'd noticed that the re module hadn't been imported, I probably wouldn't
have considered URL linking to be important enough to do so. Since I've
already written the code, however, I'll keep it.
SotBE S8: give a little more gold to player on nightmare
SotBE S14: add a village close to northeast AI ally leader's keep
SotBE S14: remove trolls from AI allies' recruit lists

Since Grüü takes off with all the trolls.  This was already done for
the player side.
Update changelog