setup-environment-internal: refactor
setup-environment-internal: refactor

Re-organize the machine selection process so that "whiptail", "dialog", and
the help message options all use the same machine and layer list (sorted by
machine).

Include the layer along with the machine for all machine listings.

Signed-off-by: Trevor Woerner <8835777cd84fba3d7873eabbbe1f2de2d3f25b00@gmail.com>

twoerner/angstrom-manifest,linaro-home/lhg-oe-manifests,koenkooi/angstrom-manifest,ndechesne/qcom-oe-manifest,96boards/oe-rpb-manifest,Angstrom-distribution/angstrom-manifest