changes all ${} vars to {{}}

On branch fix/deprecation_warnings
Changes to be committed:
  (use "git reset HEAD <file>..." to unstage)

	modified:   deploy.yml
	modified:   provision.yml
	modified:   templates/apache2-site
	modified:   vars_derived.yml
add cache_time on apt-get updates

On branch master
Your branch is up-to-date with 'origin/master'.

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	modified:   provision.yml
Merge branch 'master' into fix/deprecation_warnings

Conflicts:
	provision.yml
add none ssl option to apache config
Merge pull request #3 from pgolm/feature/apache_config

Feature/apache config