* Cleanup SP Cache code, now SP Cache only deletes sp_head objects in 
  sp_cache_flush_obsolete() invalidates all pointers to routines in the cache.
* Use new SP Cache use contract in the code.

There is no test case because it doesn't seem to be possible to cause thread races to end
the same way they end in heavy-load test. This patch removes the crash in heavy test.

into deer.(none):/home/hf/work/mysql-5.0.12281

Field_geom lack size_of method

into  mysql.com:/home/cps/mysql/trees/mysql-5.0

into  mysql.com:/home/jimw/my/mysql-5.0-clean

into  mysql.com:/home/jimw/my/mysql-5.0-clean

into  mysql.com:/home/jimw/my/mysql-4.1-clean

into  mysql.com:/home/jimw/my/mysql-4.1-clean

into  fedora.(none):/home/reggie/bk/im_patch

into  fedora.(none):/home/reggie/bk/im_patch

into  fedora.(none):/home/reggie/bk/im_patch

into mysql.com:/space/my/mysql-5.0

into deer.(none):/home/hf/work/mysql-5.0.clean

into deer.(none):/home/hf/work/mysql-4.1.clean

into mysql.com:/Users/kent/mysql/bk/mysql-5.0

  Back ported ndbcluster_support() from 5.0
  Corrected the server id handling

into mysql.com:/Users/kent/mysql/bk/mysql-4.1

  Added the blackhole storage engine to the Max builds

into deer.(none):/home/hf/work/mysql-5.0.clean

into deer.(none):/home/hf/work/mysql-4.1.9508

into deer.(none):/home/hf/work/mysql-4.1.11083

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

into mysql.com:/space/my/mysql-5.0-build

  the rpm spec file changelog