(fact-79) Don't try 'gem install json' on windows
(fact-79): Add Solaris zone facts
(fact-79) Enforce standard format for all macaddresses

Prior to this patch, the 'macaddress' fact was standardized,
but the 'macaddress_<interface>' facts were not. This patch
adds a spec test to catch this and the fix to use the same
method for both.
Merge branch 'facter-2'

Conflicts:
	lib/facter/interfaces.rb
	spec/unit/interfaces_spec.rb

For both conflicts, master won.