implementation of running a lambda in ecs

[sethvincent]

This is based in part on https://git.earthdata.nasa.gov/projects/CUMULUS/repos/ecs-lambda-runner/browse

Updated to work with step function tasks using sf.getActivityTask and related step functions API methods.

[sethvincent]

When given enough time, ecs service creation will fail with:

Service <arn> did not stabilize.

[scisco]

made two comments.

[scisco]

let's push this to the cumuluss org on docker hub?

[scisco]

to be exact, push it to: cumuluss/cumulus-ecs-task

[scisco]

Also, what is our plan for versioning here? I think we should not release with latest tag and start versioning this image.

[scisco]

@sethvincent the service ARN is probably not stabilized because it lacks the correct permissions. You have to make sure that your ec2 instance has the right to download the zip file of a given lambda.

Also you have to make sure the base image has the latest version of python 2.7

[sethvincent]

This branch can now work with a couple of outside changes:

• changing cumulus-message-adapter-js to use an env var to specify the cumulus-message-adapter location
• changing iam/cloudformation.template.yml in the deployment to add - states:SendTaskHeartbeat in the EcsRole allow actions

[sethvincent]

I've updated this with:

• circleci improvements that publish to npm and docker hub when a PR gets merged that bumps the version in package.json
• revises the dockerfile
• adds .eslintrc.json from cumulus-nasa/cumulus
• README.md updates with instructions that will help with reviewing and testing this PR
• a bunch of lint and bug fixes and a slight refactor from when I first opened this PR

[scisco]

LGTM.

It'd be useful to also add a CHANGELOG