(FACT-606) Remove Sid/Unstable from build defaults

This commit goes through the build_defaults.yaml and removes the sid and
unstable entries. Part of the reason for this removal is the lack of
testing the build but still shipping the packages and we already
build against Debian tests.
(FACT-595) Unbreak {is_,}virtual fact for OpenBSD when running on KVM.
Merge pull request #714 from clantant/FACT-606/facter-2/sid

(FACT-606) Remove Sid/Unstable from build defaults
Merge pull request #716 from jasperla/openbsd/kvm

(FACT-595) Unbreak {is_,}virtual fact for OpenBSD when running on KVM.
(FACT-547) Limit the output of prtdiag on Solaris

prtdiag is used to determine manufacturer and productname on Solaris.

If you run it on a big box like a SPARC T5 it produces a lot of output,
and might take some time, this produces timeouts leading to missing facts.

The simple addition of a pipe to head avoid prtdiag to produce it full output.

The first lines should always contain the product information.
Merge branch 'pull-689' into facter-2
(FACT-606) Remove Sid/Unstable from build defaults

This commit goes through the build_defaults.yaml and removes the sid and
unstable entries. Part of the reason for this removal is the lack of
testing the build but still shipping the packages and we already
build against Debian tests.
Merge branch 'stable' into facter-2