[illumos-Developer] HEADS UP: opensolaris.sh updated & renamed

[Garrett D'Amore]

With the integration of 

58 opensolaris.sh needs to become illumos.sh

The old opensolaris.sh env file (under usr/src/tools/env) has been
renamed to illumos.sh.  It is also updated to have values that are more
appropriate for illumos.  If you're following build directions that
indicate opensolaris.sh, be advised that you'll need to use illumos.sh
instead.

Thank you.

	- Garrett