Validate dockerfilepath in buildconfig

[surajnarwade]

This PR will resolve #594 by validating dockerfilepath based on whether
it is relative path or not.

[surajnarwade]

cc @cdrage @kadel @surajssd needs review

[kadel]

hmm, I can't make it work :-(

version: "2"

services:
    foo:
        build:
          context: "./build"
          dockerfile: /Dockerfile
        image: "tomaskral/foobar"
        command: "sleep 3600"

output:

▶ kompose --provider openshift convert --stdout
apiVersion: v1
items: null
kind: List
metadata: {}

[cdrage]

@surajnarwade same issue as @kadel

github.com/kubernetes-incubator/kompose  pr_609 ✔                                                                                                                                                                                                                            7d  
▶ ./kompose --provider=openshift convert --stdout 
apiVersion: v1
items: null
kind: List
metadata: {}

[surajnarwade]

@cdrage @kadel, can you please try now, i have updated the PR

[surajssd]

@ashetty1 can you see if this PR works for you and solve your issue then we can go ahead with it, otherwise the code LGTM, but if @ashetty1 gives a +1 we can merge it, also @surajnarwade can you please also write command line tests?

[cdrage]

Grammar error.

%q is an absolute path is better.

[cdrage]

Other than my small note (and a command line test being added), LGTM.

[surajnarwade]

@cdrage updated PR with required changes,
@ashetty1 , your review needed.

[ashetty1]

LGTM @surajnarwade

[cdrage]

LGTM