Nested joins: review modifications.

If cost(full_scan_on_shortest_covering_index) < cost(best_range_scan) <  cost(full_table_scan)
  use full_scan_on_shortest_covering_index
(before this fix best_range_scan was used)

into kite-hub.kitebird.com:/src/extern/MySQL/bk/mysql-5.0

  fix up test result.

Also added some related security tests and corrected related error messages.

into mysql.com:/home/pem/work/mysql-5.0-merge

  Correction for nested joins.

  new file
Many files:
  Nested joins added.

into mysql.com:/home/pem/work/mysql-5.0-merge

It's not possible to quote the definition according to the current sql_mode
setting, so instead we use the setting stored with the SP (that's how it's
parsed anyway), and show this setting in the SHOW CREATE output.

This fixes part of BUG#3229: Stored procedure comment causes packets out of order.

into mysql.com:/home/wax/mysql/mysql-5.0service

into mysql.com:/home/pem/work/mysql-5.0-merge

Not finished, will not be pushed until additional fixes have been made.

Fixed an incorrect optimizer choice for ror-intersect(key, clustered_primary)
Typo bug fixed in multitable update

 * Fixed test results.

 * Fixed a problem with wrong query results for partially covering keys in ROR-index_merge
 * ROR-intersection retrieval plan choice algorithm now uses less disk IO
   - and properly processes clustered PK range scans 
 * Fixed several minor range optimizer problems
 * Added more comments
 * Code cleanup

 BUG#1863: CREATE TABLE in Stored Procedure sometimes crashes on repeated calls.
 BUG#2656: select with join in stored procedure: erroneous result on 2nd call.
 BUG#3426: IF x IS NULL in stored procedure fails on second call within connection.
 BUG#3448: Stored Procedures with inner joins possible bug.
 BUG#3734: Stored procedure returns wrong rows with fulltext parameter.
 BUG#3863: Stored procedure crash when incrementing variable in a loop.

(And corrected the row count output to the client after CALL)

into sanja.is.com.ua:/home/bell/mysql/bk/work-sp2_bak-5.0

into mysql.com:/home/pem/work/mysql-5.0-merge

into mysql.com:/home/jonas/src/mysql-4.1

into sanja.is.com.ua:/home/bell/mysql/bk/work-sp2-5.0