SLOW_WAR has issues:
* The check whether the attacker old-owns the attacked sector is
broken, because att_abort() uses sect.sct_oldown uninitialized.
Spotted by the Clang Static Analyzer.
* Its implementation in setrel() is somewhat scary. It's actually
okay, because that part of setrel() only runs within decl(). Other
callers don't reach it: update_main() because player->god != 0
there, and the rest because they never pass a rel < HOSTILE.
* Documentation is a bit vague.
SLOW_WAR hasn't been used in a public game in years. Fixing it is not
worth it, so remove it instead.
(all): Depend on info.
Flatten info directory. This undoes the move to one subdirectory per
chapter, which was done during Empire 2. The structure doesn't buy us
much, as the info name space is flat, and it complicates makefiles.
Overhaul info.pl:
- It now wants to run in the root of the build tree.
- Information on source files and subjects is now stored in makefiles,
thus info.pl no longer picks up random junk from the file system.
- Clean up Perl anachronisms, in particular use subroutine arguments and
results rather than global variables where convenient.
- Change format of diagnostics to the common format used by GNU tools,
so that Emacs and the like can parse it.
- Catch missing .SA.
- When creating a new subject file, cowardly refuse to overwrite an
existing file.
- Subject files contain topics sorted by chapter, then by name. The
order of chapters used to depend on how Perl sorts hash keys. Fix
it.
