- Removed use of mysql->extra_info
 - Removed unused function send_records_num


VC++Files/winmysqladmin/mysql.h:
  Comment extra_info as not used anymore
client/mysqlshow.c:
  Remove use of extra info. Instead read number of records in table using SELECT COUNT(*)
include/mysql.h:
  Comment extra_info as not used anymore
libmysqld/lib_sql.cc:
  Removed unused function send_records_num
sql-common/client.c:
  Remove use of extra_info since number of records is not sent in the protocol anymore
sql/protocol.cc:
  Removed unused function send_records_num
sql/protocol.h:
  Removed unused function send_records_num