zip tool for google Container Builder

To use in your project step

sudo docker build -t gcr.io/[PROJECT_ID]/zip-tool
sudo gcloud docker -- push gcr.io/[PROJECT_ID]/zip-tool

Add below step in you cloudbuild.yaml

steps:
- name: 'gcr.io/[my-project-id]/zip-tool'
  args: [ '-x', '/.git*', '-r', 'zipfile.zip', '.']

Refer examples/cloudbuild.yaml for build step details