moved fail-safe replication routines from sql_repl.cc to repl_failsafe.cc
write start event only in the first log


client/mysqlbinlog.cc:
  work to enable reading 3.23 logs
libmysql/Makefile.shared:
  added mf_iocache2 to libmysqlclient - needed for mysqlbinlog
mysql-test/mysql-test-run.sh:
  added --start-and-exit
mysql-test/r/rpl000002.result:
  result clean-up
mysql-test/r/rpl000016.result:
  result update
mysql-test/r/rpl_log.result:
  result update
mysql-test/t/rpl000016.test:
  test cleanup
mysys/mf_iocache.c:
  fixed new bug
sql/log.cc:
  write start event only on server start or after reset master
sql/log_event.cc:
  work to enable reading 3.23 log format
sql/log_event.h:
  work to enable reading 3.23 format
sql/repl_failsafe.cc:
  code restructuring
sql/repl_failsafe.h:
  re-organized code
sql/slave.cc:
  check master version
sql/slave.h:
  old_format member
sql/sql_class.h:
  allow user to specify io cache type
  need_start_event member to allow writing start event only in the first log
sql/sql_parse.cc:
  code re-organization
sql/sql_repl.cc:
  code reorganization
sql/sql_repl.h:
  reorganized code