ci: update build script, integrate with circleci

[gszr]

Summary

• Update build script, automating builds for all distributions and architectures
• Integrate build script with CircleCI

Releases are automatically built and pushed to Bintray whenever a tag is pushed.

[yskopets]

Hi @gszr .
Great work! Thanks a lot.

I've left a few comments on source files.
Additionally, I'm also wondering:

1. would it be possible to setup a test repo on bintray so that we could test these scripts before merging into master ?
2. I don't see handling of Docker images. will it be a separate PR ?

[gszr]

Will do one more test release on top of the "wip" commit (changing the Bintray repository to kuma-tests) - it'll be pushed to https://bintray.com/kong/kuma-tests.

Edit: test was completed, commit reverted.

[dhruv]

Actually, we need the envoy binaries in the distributions.

We need envoy binaries

[gszr]

Additionally, I'm also wondering:
1. would it be possible to setup a test repo on bintray so that we could test these scripts before merging into master ?

I've been testing on https://bintray.com/kong/kuma-tests.

2. I don't see handling of Docker images. will it be a separate PR ?

Yes, it will be done in a separate PR.

[yskopets]

@gszr awesome shell script, by the way.

Thanks a lot!