Remove usage of !$ from mysql-tests

Added protocol::flush() for easier embedded-server code
Increase block allocation variables a bit as they where a bit too small for MySQL 4.1
Added option --silent to client_test


client/mysqltest.c:
  Removed compiler warning
  Fixed identation & comments from earlier push
  Renamed variable 'disable_abort_on_error' to 'abort_on_error'
  Ensure that '$mysql_errno' also with --ps-protocol
include/mysql_com.h:
  Removed special handling of net_flush for embedded server
mysql-test/r/mysqltest.result:
  Remove usage of !$ in tests
mysql-test/t/client_test.test:
  Use --silent
mysql-test/t/comments.test:
  Remove usage of !$ in tests
mysql-test/t/join_outer.test:
  Remove usage of !$ in tests
mysql-test/t/key.test:
  Remove usage of !$ in tests
mysql-test/t/mysqltest.test:
  Remove usage of !$ in tests
mysql-test/t/show_check.test:
  Remove usage of !$ in tests
mysql-test/t/temp_table.test:
  Remove usage of !$ in tests
mysql-test/t/type_ranges.test:
  Remove usage of !$ in tests
sql/mysqld.cc:
  Increase block allocation variables a bit as they where a bit too small for MySQL 4.1
sql/net_serv.cc:
  Remove special usage of net_flush in embedded server
sql/protocol.cc:
  Added protocol::flush() for easier embedded-server code
sql/protocol.h:
  Added protocol::flush() for easier embedded-server code
sql/sql_prepare.cc:
  Added protocol::flush() for easier embedded-server code
  Remove one extra flush() for prepared statements
sql/sql_show.cc:
  Added protocol::flush() for easier embedded-server code
tests/client_test.c:
  Added option --silent

mysql-test/t/comments.test

@@ -5,7 +5,8 @@
 select 1+2/*hello*/+3;
 select 1 /* long
 multi line comment */;
-!$1065 ;
+--error 1065
+ ;
 select 1 /*!32301 +1 */;
 select 1 /*!52301 +1 */;
 select 1--1;