testfail: Add t5513-fetch-track.sh

Without the patch from David Turner, it failed on v2.0.1-474-g72c7794
using Ubuntu Studio 13.10:

  *** t5513-fetch-track.sh ***
  ok 1 - setup
  not ok 2 - fetch
  #
  #               (
  #                       cd other && git fetch origin &&
  #                       test "$(git for-each-ref --format="%(refname)")" = refs/remotes/b/one
  #               )
  #
  # failed 1 among 2 test(s)
  1..2
  make[2]: *** [t5513-fetch-track.sh] Error 1
  make[2]: Leaving directory `/home/sunny/src/other/git/build-git/t'
  make[1]: *** [test] Error 2
  make[1]: Leaving directory `/home/sunny/src/other/git/build-git/t'
  make: *** [test] Error 2

Don't know if it's reproducible or if something strange happened during
the build. We'll see.

ae36f0c8-0760-11e4-ac90-c80aa9e67bbd