Cherry-pick Pipfile detection fix for 2018.2.1#1002

Merged

DonJayamanne merged 2 commits intomicrosoft:release-2018.2from

brettcannon:release-2018.2

Mar 9, 2018

Commits on Mar 9, 2018

Detect pipenv by looking for Pipfile, not pipfile (#994)

wjt
authored and
brettcannon
committed
Prep for 2018.2.1
brettcannon
committed