[SAC] Updating Member list

[Alex Mandel]

For sanity of those involved I started updating the SAC member list to
reflect the current reality. e.g. if you've helped with something in
recent memory I added you to the list.
http://wiki.osgeo.org/wiki/SAC#Members

Please add people who are missing, or additional roles people play. This
will help us know who is likely to handle particular issues when they
come up.

Thanks,
Alex