Features: Record for VS 2017 through 15.6

VS 15.3 has more features than we recorded in commit v3.7.0-rc1~156^2~2
(Features: Record features for VS 15 Preview 4, 2016-09-05).

While at it, update comments and simplify some cases.
15 jobs for patch-1
latest
Status Name Job ID Coverage
  External
passed ghostflow-branch-check-master

passed ghostflow-commit-check

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager