kompose up seems to not use the build context's .dockerignore file

[bianchidotdev]

When attempting to run kompose up, I run into a build error referenced in issue 656 saying:

FATA Error while deploying application: k.Transform failed: Unable to build Docker image for service wrangler: Unable to create a tarball: read /Users/michaelbianchi/workspace/mercury-platform/wrangler/_build/dev/lib/certifi/ebin: is a directory

While the other issue states kompose doesn't handle symlinks well, this directory should never be included in the build context due to being ignored in the .dockerignore file. If kompose is going to handle the building of images, it should respect things handled by docker-compose such as .dockerignore.

It's also possible I have this poorly setup, but everything else looks right. kompose convert works. Source code is held in https://github.com/michaeldbianchi/mercury-platform

Verbose:

 λ on minikube in ~/workspace/mercury-platform on  master [!?] kompose -f docker-compose.yml -v up
DEBU Docker Compose version: 3
WARN Volume mount on the host "/Users/michaelbianchi/workspace/mercury-platform/data" isn't supported - ignoring path on the host
INFO Build key detected. Attempting to build image 'michaeldbianchi/wrangler:dev'
DEBU Build image working dir is: /Users/michaelbianchi/workspace/mercury-platform
DEBU Build image context is: /Users/michaelbianchi/workspace/mercury-platform/wrangler
INFO Building image 'michaeldbianchi/wrangler:dev' from directory 'wrangler'
DEBU Created temporary file /var/folders/65/6cd8mczj1d198sxvrq2vb7v40000gp/T/kompose-image-build-475960662 for Docker image tarballing
FATA Error while deploying application: k.Transform failed: Unable to build Docker image for service wrangler: Unable to create a tarball: read /Users/michaelbianchi/workspace/mercury-platform/wrangler/_build/dev/lib/certifi/ebin: is a directory

[bianchidotdev]

Note that if I delete the _build and deps directories (which are in the .dockerignore), kompose up worked just fine. However, since elixir builds creates directories with symlinks, it makes kompose almost unusable since every time I run tests or a dev server, those directories are populated.

[hangyan]

close by #1297