Revert "switch to using gliderlabs/alpine base image"
Revert "switch to using gliderlabs/alpine base image"

This reverts commit d458f15a4000bbf5d0a18af405525d4d9eb810c3.

This did not work properly.

baszalmstra/semver-resource,concourse/semver-resource,concourse/semver-resource,baszalmstra/semver-resource