I'd like to have this one finished to conclude scorelog changes for 2.5.

Do you happen to already have any utilities to process these new scorelog formats?

- New functions with empty function header are no longer accepted. Please add function header for the functions you are adding
- in one comment you change "iff" (if and only if) to "if" Is that correct (can the function sometimes return TRUE even if reading the file failed)?

> Freeciv 2.3.2.

Not strictly a bugfix, and more importantly changes file format potentially breaking existing tools parsing it, so cannot be accepted to stable brances. Setting 2.5 target.

I introduced these tags to the scorelog file:
taxout: gold accumulated per turn;
cunits: amount of civilian units owned.

The scorelog command "addplayer" now logs "username" and "ranked_username", in addition to player's "name"; it's format becomes:
addplayer <turn> <player-id> <name> , <username> , <ranked_username>
adds a player starting at the given turn (inclusive)
<player-id> is a number which can be reused
<name> may contain whitespaces
<username> may contain whitespaces
<ranked_name> may contain whitespaces

The white space preceding commas is taken in consideration of sscanf() in report.c, line 1129, Freeciv 2.3.2.

Patch has been tested.