use MTR_MEM environment variable

Improve log message

into  neptunus.(none):/home/msvensson/mysql/mysql-4.1-maint

Fixes:
- Bug #24089: Race condition in fil_flush_file_spaces()

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/41

into  neptunus.(none):/home/msvensson/mysql/mysql-4.1-maint

Pass location of charsets dir to mysqltest to avoid using the charsetdir locally installed on machine. 

into  mysql.com:/Users/kent/mysql/bk/lic/my41-lic

  Added LICENSE.mysql, removed LICENSE.doc README.NW.
  Removed obselete section about MySQLEULA.txt and README.NW.
README:
  Added reference to the EXCEPTIONS-CLIENT file.
  Changed reference to the commercial license file.
  Corrected references into chapters in the manual.
.del-MySQLEULA.txt~4a1afd9284f9be5a:
  Delete: Docs/MySQLEULA.txt

 - Readd --skip-bdb when valgrinding

Correct faulty commit, the opt_tastcase_timeout value is in minutes, to it need to be multiplied with 60 before ping passed to mtr_timer_start 

into  neptunus.(none):/home/msvensson/mysql/mysql-4.1-maint

Make --mem settable with environment variable MTR_MEM and make it possible to pass the directory to use. I.e --mem=<directory>  

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-4.1-maint

  
The Item_func_mod objects never had maybe_null set, so users had no reason 
to expect that they can be NULL, and may therefore deduce wrong results.
Now, set maybe_null.

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-4.1-maint

into  shellback.(none):/home/msvensson/mysql/mysql-4.1-maint

  Raise version number to 4.1.23

into  kpdesk.mysql.com:/home/thek/dev/mysql-4.1-maint

- 'false' not defined in C, use FALSE instead.

into  mysql.com:/usr/home/ram/work/bug22913/my41-bug22913

We don't check for errors that may occur during data printing.

into  bodhi.local:/opt/local/work/mysql-4.1-runtime

into  shellback.(none):/home/msvensson/mysql/mysql-4.1-maint

into  shellback.(none):/home/msvensson/mysql/mysql-4.1-maint

into  kpdesk.mysql.com:/home/thek/dev/mysql-4.1-maint

 - Only read *.pid
 - Only allow it to contain a number 

- Because my_seek actually is capable of returning an error code we should
  exploit that in the best possible way.
- There might be kernel errors or other errors we can't predict and capturing
  the return value of all system calls gives us better understanding of
  possible errors.