website: Add Python deploy guide outline

Signed-off-by: Blaž Hrastnik <blaz.hrast@gmail.com>
util/release: Support custom Docker registry & user

Signed-off-by: Lewis Marshall <lewis@lmars.net>
pinkerton: Support BasicAuth with Docker endpoints

Signed-off-by: Lewis Marshall <lewis@lmars.net>
website: Document releasing Flynn

Signed-off-by: Lewis Marshall <lewis@lmars.net>
util/packer: Handle existing fuse group

Signed-off-by: Lewis Marshall <lewis@lmars.net>
Merge pull request #387 from flynn/fix-packer-build

util/packer: Handle existing fuse group
Merge pull request #382 from flynn/custom-docker-repository

Custom Docker registry / user
website: Add an the Python deploy guide.

Signed-off-by: Blaž Hrastnik <blaz.hrast@gmail.com>
Merge pull request #367 from flynn/how-to-deploy-python

website: "How To Deploy Python" page
website: Clean up 'How To Deploy Go'

Signed-off-by: Dominic Serio <dominic@flynn.io>