to use constants instead of local variables. Also, change the permissions
so that they are stricter in general, and work better under suexec.
This also fixes the problem that dependency graphs didn't work under
suexec, and adds a "web" directory by default to Extensions created with
extension/create.pl.
r=mkanat, a=mkanat (module owner)

Bug 542328: Make extensions/create.pl give the extension's lib/Util.pm module a correct package name
Patch by Tiago Mello <timello@gmail.com> r=mkanat, a=mkanat

Patch by Max Kanat-Alexander <mkanat@bugzilla.org> (module owner) a=mkanat