mariadb/myisam/ftbench

1. should be run from myisam/ftbench/
2. myisam/ftdefs.h should NOT be locked (bk get, not bk edit!)
3. there should be ./data/ subdir with test collections, files:
     test1.d
     test1.q
     test1.r
     test2.d
     test2.q
     test2.r
   where test1, test2, etc - are arbitrary test names

  *.[dq] files contain documents/queries one item per line.

   *.r files have the structure:
   1 16 .....blablabla
   1 09 .....blablabla
   2 116 .....blablabla
   ...

  that is /^\d+\s+\d+/
  and are sorted by the first number (not necessarily by the second)
   
4. there should be ./t/ subdir with test directories

  ./t
  ./t/BEST/
  ./t/testdir1/
  ./t/testdir2/
  ...

  there *must* be ./t/BEST/ subdir or a symlink to one of other dirs in ./t
  all other names (besides BEST) can be arbitrary

  all test results are compared with BEST results.
  
  test directories may contain ftdefs.h, my.cnf, ft_mode
  (the last one is used as in ... MATCH ... AGAINST ("..." $ft_mode) ...)
  NOTE: all *.out files in test directories will NOT be overwritten!
  delete them to re-test

5. run ./ft-test-run.sh
6. go make some coffee