Remove unused file multiplay/maps/4c-rush/templ.bjo.
Keep a copy of our log filename that we use to work around an obscure bug(?)
in compiler flags (windows (mingw) only).

Should now correctly show the log filename on crashes in the dialog.
Fix false positive in the Coverity static analysis tool.

The array will never be MAX_PLAYERS (11) and overrun it, since the loop goes
up to indexLen which is < MAX_PLAYERS.

This fixes a rash of asserts of 'Found no player position for player X' where
X is missing because of the false positive above, which cut the array short.

refs: cea585162d631e8a6360153a28d7825405dd9de3
Merge branch 'bugfixes' into 3.1