First version of new authentification procedure: now authentification is one-stage (instead of two-stage in 4.1)

For now following tasks have been done:
- PASSWORD() function was rewritten. PASSWORD() now returns SHA1
  hash_stage2; for new passwords user.password contains '*'hash_stage2; sql_yacc.yy also fixed; 

- password.c: new functions were implemented, old rolled back to 4.0 state

- server code was rewritten to use new authorization algorithm (check_user(), change
  user, and other stuff in sql/sql_parse.cc)

- client code was rewritten to use new authorization algorithm
  (mysql_real_connect, myslq_authenticate in sql-common/client.c)

- now server barks on 45-byte-length 4.1.0 passwords and refuses 4.1.0-style
  authentification. Users with 4.1.0 passwords are blocked (sql/sql_acl.cc)

- mysqladmin.c was fixed to work correctly with new passwords

Tests for 4.0-4.1.1, 4.1.1-4.1.1 (with or without db/password) logons was performed;
mysqladmin also was tested. Additional check are nevertheless necessary.

into sanja.is.com.ua:/home/bell/mysql/bk/work-union-4.1

into serg.mylan:/usr/home/serg/Abk/mysql-4.1

(resolving fields of reduced subselect)

into sanja.is.com.ua:/home/bell/mysql/bk/work-cset-4.1

test moved to other bug 

into serg.mylan:/usr/home/serg/Abk/mysql-4.1

into sanja.is.com.ua:/home/bell/mysql/bk/work-order-4.1

into teton.kitebird.com:/home/paul/mysql-4.1

into rhols221.adsl.netsonic.fi:/home/my/bk/mysql-4.1

into mysql.com:/space/my/mysql-4.1-build

  A better comment

and comparison was done binary. Now, a binary string wins a character sting 
taking in account their derivation. That means a character field wins a
binary literal and comparison is done according to the character field
collation, not binary. 

into teton.kitebird.com:/home/paul/mysql-4.1

into serg.mylan:/usr/home/serg/Abk/mysql-4.1

  Change mode to -rw-rw-r--

REPLACE() now processed arguments collations according to standard

fixed BUG #726

into mysql.r18.ru:/usr/home/bk/mysql-4.1

  My stupid typo fix

into bar.mysql.r18.ru:/usr/home/bar/mysql-4.1

now process arguments according to standard SQL collation determation
rules.

into mysql.r18.ru:/usr/home/bk/mysql-4.1