Fix of the bug, which causes crash on Windows because of missing "history" file.
After first run of git AC version "config/history" file doesn't exist, what causes crash of  Windows AC version,  which can't find this file.
Commit just adds checking, whether this file exists - "if(!histbuf) return;" in loadhistory() .
Commit fixes also location of some brackets and spaces, in order to keep proper AC style.