Fix 'path does not exist' error when using Windows + --check.

Merge pull request #123 from aerys/fix/windows-check-path-does-not-exist

Fix 'path does not exist' error when using Windows + --check.

Missed brackets fix

Missed brackets fix

use el7 version on el8

Since those packages work for that version and they are not there 'yet' use this instead.

Add clone_url option

Add clone_url option

Support system-mode and user-mode

Support system-mode and user-mode

Add support for proxy

Fix for a typo in the regexp for url when inserting the environment
Addition of 'pre_clone_script' which is needed for installation behind a proxy

Making s3 access key and secret key as optional

Making s3 access key and secret key as optional

Fix become directives

Fix become directives

Fix default coordinator URL

Fix default coordinator URL

provide support for autoscaling setup on AWS with docker-machine

Should now be ok ;p