run at startup"

The server returned an error when trying to execute init-file with a 
stored procedure that could return multiple result sets to the client. 
A stored procedure can return multiple result sets if it contains 
PREPARE, SELECT, SHOW and similar statements.
   
The fix is to set client_capabilites|=CLIENT_MULTI_RESULTS in
sql_parse.cc:handle_bootstrap(). There is no "client" really, so 
nothing is ever sent. This makes init-file feature behave consistently: 
the prepared statements that can be called directly in the init-file 
can be used in a stored procedure too.

Re-committed the patch originally submitted by Per-Erik after review.


mysql-test/Makefile.am:
  Fix re-make without make clean.
mysql-test/r/init_connect.result:
  Updated results (a test case for Bug#17843)
mysql-test/r/init_file.result:
  Updated results (a test case for Bug#17843)
mysql-test/std_data/init_file.dat:
  Add test coverage for new features added in 5.0. Note, that what can 
  be done in init_file is very limited as it does not support any other
  delimiter except ';' -- only "one liners" and no multiple statement 
  procedures. Also, this is executed with a dummy user "boot@", which 
  calls for the use of DEFINER clause.
mysql-test/t/init_connect.test:
  Add test coverage for new features added in 5.0.
mysql-test/t/init_file.test:
  Add test coverage for new features added in 5.0 --
  stored routines, views, triggers. The actual tests are in 
  std_data/init_file.dat, here we just check the results and clean up.
sql/sql_class.cc:
  Initialize Security_context::priv_host to an empty string:
  when executing an init-file, sql_parse.cc:get_default_definer()
  will use this for the value of the definer if it's not set in the query.
sql/sql_parse.cc:
  Set CLIENT_MULTI_RESULTS in handle_bootstrap(), to make prepared
  statements work in stored procedures called from init-file.