USN-3464-1: Wget vulnerabilities

[Cryptophobia]

From @Bregor on October 30, 2017 8:43

Package wget should be upgraded in quay.io/deis/slugbuilder image due to USN-3464-1

Copied from original issue: deis/slugbuilder#145

[Cryptophobia]

From @stuszynski on October 30, 2017 15:9

I made an issue on Heroku stack images repository: heroku/base-images#84