(updated) Protocol_cursor class.
Also did some bug fixes.


Docs/sp-imp-spec.txt:
  Added CURSOR docs (and fixed typos)
Docs/sp-implemented.txt:
  Updated for CURSORs
include/mysqld_error.h:
  New error codes/messages for CURSORs
libmysqld/Makefile.am:
  SP cursors now needs this.
mysql-test/r/sp-error.result:
  New tests for cursors.
mysql-test/r/sp.result:
  New tests for cursors.
mysql-test/t/sp-error.test:
  New tests for cursors.
mysql-test/t/sp.test:
  New tests for cursors.
sql/protocol.cc:
  We now always have Protocol_cursor (SPs use it)
sql/protocol.h:
  Fixed bugs in Protocol_cursor (for SPs)
sql/protocol_cursor.cc:
  Fixed bugs in Protocol_cursor (for SPs)
sql/share/czech/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/danish/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/dutch/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/english/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/estonian/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/french/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/german/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/greek/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/hungarian/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/italian/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/japanese/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/korean/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/norwegian-ny/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/norwegian/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/polish/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/portuguese/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/romanian/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/russian/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/serbian/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/slovak/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/spanish/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/swedish/errmsg.txt:
  New error codes/messages for CURSORs
sql/share/ukrainian/errmsg.txt:
  New error codes/messages for CURSORs
sql/sp_head.cc:
  Added cursor support.
  Also fixed problems with item_lists, where pointers and ref_pointer_arrays.
sql/sp_head.h:
  Added cursor support
sql/sp_pcontext.cc:
  Added cursor support
sql/sp_pcontext.h:
  Added cursor support
sql/sp_rcontext.cc:
  Added cursor support, in particular the new sp_cursor class.
sql/sp_rcontext.h:
  Added cursor support, in particular the new sp_cursor class.
sql/sql_lex.h:
  We sometimes need to copy item_lists in LEX when executing substatements in SPs
sql/sql_yacc.yy:
  Added minimal cursor support (not the full syntax yet).