DO NOT MERGE TO 4.1: add code for automatic downgrade 4.1.1 -> 4.0 if the user has not created multiple tablespaces yet


innobase/include/srv0srv.h:
  DO NOT MERGE TO 4.1: add code for automatic downgrade 4.1.1 -> 4.0 if the user has not created multiple tablespaces yet
innobase/include/trx0sys.h:
  DO NOT MERGE TO 4.1: add code for automatic downgrade 4.1.1 -> 4.0 if the user has not created multiple tablespaces yet
innobase/ibuf/ibuf0ibuf.c:
  DO NOT MERGE TO 4.1: add code for automatic downgrade 4.1.1 -> 4.0 if the user has not created multiple tablespaces yet
innobase/srv/srv0start.c:
  DO NOT MERGE TO 4.1: add code for automatic downgrade 4.1.1 -> 4.0 if the user has not created multiple tablespaces yet
innobase/trx/trx0sys.c:
  DO NOT MERGE TO 4.1: add code for automatic downgrade 4.1.1 -> 4.0 if the user has not created multiple tablespaces yet