binary SHOW CREATE TABLE or SELECT FROM I_S.

The problem is that mysqldump generates incorrect dump for a table
with non-ASCII column name if the mysqldump's character set is
ASCII.

The fix is to:
  1. Switch character_set_client for the mysqldump's connection
  to binary before issuing SHOW CREATE TABLE statement in order
  to avoid conversion.
  
  2. Dump switch character_set_client statements to UTF8 and back
  for CREATE TABLE statement.


client/mysqldump.c:
  1. Switch character_set_client for the mysqldump's connection
  to binary before issuing SHOW CREATE TABLE statement in order
  to avoid conversion.
  
  2. Dump switch character_set_client statements to UTF8 and back
  for CREATE TABLE statement.
mysql-test/r/mysqldump-max.result:
  Update result file.
mysql-test/r/mysqldump.result:
  Update result file.
mysql-test/r/openssl_1.result:
  Update result file.
mysql-test/r/show_check.result:
  Update result file.
mysql-test/t/show_check.test:
  Test case:
    - create a table with non-ASCII column name;
    - dump the database by mysqldump using ASCII character set;
    - drop the database;
    - load the dump;
    - check that the table has been re-created properly.