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.