Fix and improve improve circleci

[alexdashkov]

TLDR:

• A full refactoring of a CircleCI config to avoid troubles with cache.
• Remove test that uses celery in async mode

CI:

CircleCI has 3 jobs: tests, build, deploy

build_and_test (executes for each branch):

It's a step that up a full environement and runs tests. Instead of docke venv is cached (3sec instead of 30)

build_image (executes only for the master):

Build a docker image using cache from the latest pushed container.

deploy(executes only for the master):

Deploy image from the previous step to the dev cluster 

[shawnlauzon]

@alexdashkov It seems to be stuck waiting ...

[alexdashkov]

@shawnlauzon I separated tests_and_build to the different jobs tests and build. So this job doesn't exist anymore. I suppose that the github config should be changed.

[shawnlauzon]

@alexdashkov I just changed the expectations, and it still doesn't work. I just see that tests runs twice and build not at all

[shawnlauzon]

Thanks for that information @alexdashkov