This fixes a bug found by bdb.test
Fixes a portability issue with bdb tables


mysql-test/include/varchar.inc:
  Fix test to be reproducable
  (Either key v or v_2 could be used here)
mysql-test/r/bdb.result:
  Fix test to be reproducable
  (Either key v or v_2 could be used here)
mysql-test/r/myisam.result:
  Fix test to be reproducable
  (Either key v or v_2 could be used here)
sql/table.cc:
  Fix max_key_length and max_unique_length to take into account varchar and null extra lengths
  This fixes a bug found by bdb.test