patch applied (testsuite): Use letters to allow output to be matched up with the code more easily

[Ian Lynagh]

Thu May  3 12:26:04 PDT 2007  Ian Lynagh <igloo at earth.li>
  * Use letters to allow output to be matched up with the code more easily

    M ./tests/ghc-regress/numeric/should_run/arith005.hs -20 +20
    M ./tests/ghc-regress/numeric/should_run/arith005.stdout -20 +20
    M ./tests/ghc-regress/numeric/should_run/arith005.stdout-ws-64 -20 +20