installPackage should create and update "dir", too

  /Users/dan/Library/Application Support/Macaulay2/local/share/info:
  total used in directory 8 available 128477364
  drwxr-xr-x  3 dan  staff   102 Jul 16 15:12 .
  drwxr-xr-x  5 dan  staff   170 Jul 16 14:48 ..
  -rw-r--r--  1 dan  staff  3919 Jul 16 15:12 OpenMath.info

