fixed race condition in binary log auto-rotation
get rid of extention in binary log to avoid non-rotatable logs


client/mysqltest.c:
  fixed uninitialized use of variable bug
sql/log.cc:
  fixed race condition on binary log auto-rotate
sql/mysqld.cc:
  get rid of extention on binary log
sql/sql_class.h:
  argument to new file (inside_mutex)