cleanups
better, charset-dependent, ft_max_len_for_sort value


myisam/ftdefs.h:
  better ft_max_len_for_sort value
myisam/mi_check.c:
  better, charset-dependent, ft_max_len_for_sort value
myisam/myisamchk.c:
  unused value from enum removed
myisam/sort.c:
  cleanup
sql/mysql_priv.h:
  cleanup
sql/mysqld.cc:
  cleanup
sql/sql_acl.cc:
  cleanup
sql/tztime.cc:
  cleanup
strings/ctype-utf8.c:
  bug in my_strnncoll_utf8 (and friends) fixed