make lint should fail CI

[clburlison]

When the lint tasks (specifically the golint command) fails we should exit 1. The only gotcha with this is the failure needs to allow the task to run first then check and fail. This way users can get the full golint output.

#!/bin/bash -eo pipefail
make lint
vendor/github.com/groob/mackit/example/password.go:24:2: comment not terminated
vendor/github.com/groob/mackit/example/password.go:38:3: expected '}', found 'EOF'
All .go files formatted correctly
/go/src/github.com/clburlison/bakeit/src/setup_linux.go:9:1: exported function Setup should have comment or be unexported
/go/src/github.com/clburlison/bakeit/src/chef/client.go:1:1: package comment should be of the form "Package chef ..."
/go/src/github.com/clburlison/bakeit/src/config/config.go:66:2: exported var ChefClientLogLevel should have comment or be unexported
/go/src/github.com/clburlison/bakeit/src/config/config.go:68:2: comment on exported var ChefClientSSLVerifyMode should be of the form "ChefClientSSLVerifyMode ..."
/go/src/github.com/clburlison/bakeit/src/node/node.go:4:6: type name will be used as node.NodeInfoObject by other packages, and that stutters; consider calling this InfoObject
/go/src/github.com/clburlison/bakeit/src/serial/serial_linux.go:3:1: exported function GetSerialNumber should have comment or be unexported

See https://circleci.com/gh/clburlison/bakeit/37