FAQ improvements

[Davi Leal]

Index reorganized:

    http://gnuherds.org/faq



Added new question: "Who can join or register?"

    http://gnuherds.org/faq#membership



Added the below "Software distributions" FS criteria:

  For software distributions, they must not include BLOBs,
  for example inside the Linux kernel, or provide easy access
  to Non-Free Software, even if the default is all Free Software.

    http://gnuherds.org/faq#FS_criteria

  If nobody disagree or comment about it, we will check
  with RMS to certify such addition to the criteria.



I am not sure if there are mistakes