Merge branch 'docs/ci-dpl-example' into 'master'

Update dpl CI example

Closes #3129

See merge request !9872

doc/ci/examples/deployment/README.md

-## Using Dpl as deployment tool
-Dpl (dee-pee-ell) is a deploy tool made for continuous deployment that's developed and used by Travis CI, but can also be used with GitLab CI. 
+# Using Dpl as deployment tool
 
-**We recommend to use Dpl, if you're deploying to any of these of these services: https://github.com/travis-ci/dpl#supported-providers**.
+[Dpl](https://github.com/travis-ci/dpl) (dee-pee-ell) is a deploy tool made for
+continuous deployment that's developed and used by Travis CI, but can also be
+used with GitLab CI.
 
-### Requirements
-To use Dpl you need at least Ruby 1.8.7 with ability to install gems.
+>**Note:**
+We recommend to use Dpl if you're deploying to any of these of these services:
+https://github.com/travis-ci/dpl#supported-providers.
+
+## Requirements
+
+To use Dpl you need at least Ruby 1.9.3 with ability to install gems.
+
+## Basic usage
+
+Dpl can be installed on any machine with:
 
-### Basic usage
-The Dpl can be installed on any machine with:
 ```
 gem install dpl
 ```
 
-This allows you to test all commands from your shell, rather than having to test it on a CI server.
+This allows you to test all commands from your local terminal, rather than
+having to test it on a CI server.
 
 If you don't have Ruby installed you can do it on Debian-compatible Linux with:
+
 ```
 apt-get update
 apt-get install ruby-dev
@@ -26,9 +36,10 @@ To use it simply define provider and any additional parameters required by the p
 For example if you want to use it to deploy your application to heroku, you need to specify `heroku` as provider, specify `api-key` and `app`.
 There's more and all possible parameters can be found here: https://github.com/travis-ci/dpl#heroku
 
-```
+```yaml
 staging:
-  type: deploy
+  stage: deploy
+  script:
   - gem install dpl
   - dpl --provider=heroku --app=my-app-staging --api-key=$HEROKU_STAGING_API_KEY
 ```
@@ -37,14 +48,17 @@ In the above example we use Dpl to deploy `my-app-staging` to Heroku server with
 
 To use different provider take a look at long list of [Supported Providers](https://github.com/travis-ci/dpl#supported-providers).
 
-### Using Dpl with Docker
+## Using Dpl with Docker
+
 When you use GitLab Runner you most likely configured it to use your server's shell commands.
 This means that all commands are run in context of local user (ie. gitlab_runner or gitlab_ci_multi_runner).
 It also means that most probably in your Docker container you don't have the Ruby runtime installed.
 You will have to install it:
-```
+
+```yaml
 staging:
-  type: deploy
+  stage: deploy
+  script:
   - apt-get update -yq
   - apt-get install -y ruby-dev
   - gem install dpl
@@ -53,24 +67,31 @@ staging:
   - master
 ```
 
-The first line `apt-get update -yq` updates the list of available packages, where second `apt-get install -y ruby-dev` install `Ruby` runtime on system.
+The first line `apt-get update -yq` updates the list of available packages,
+where second `apt-get install -y ruby-dev` installs the Ruby runtime on system.
 The above example is valid for all Debian-compatible systems.
 
-### Usage in staging and production
-It's pretty common in developer workflow to have staging (development) and production environment.
-If we consider above example: we would like to deploy `master` branch to `staging` and `all tags` to `production` environment.
+## Usage in staging and production
+
+It's pretty common in the development workflow to have staging (development) and
+production environments
+
+Let's consider the following example: we would like to deploy the `master`
+branch to `staging` and all tags to the `production` environment.
 The final `.gitlab-ci.yml` for that setup would look like this:
 
-```
+```yaml
 staging:
-  type: deploy
+  stage: deploy
+  script:
   - gem install dpl
   - dpl --provider=heroku --app=my-app-staging --api-key=$HEROKU_STAGING_API_KEY
   only:
   - master
-  
+
 production:
-  type: deploy
+  stage: deploy
+  script:
   - gem install dpl
   - dpl --provider=heroku --app=my-app-production --api-key=$HEROKU_PRODUCTION_API_KEY
   only:
@@ -78,21 +99,28 @@ production:
 ```
 
 We created two deploy jobs that are executed on different events:
+
 1. `staging` is executed for all commits that were pushed to `master` branch,
 2. `production` is executed for all pushed tags.
 
 We also use two secure variables:
+
 1. `HEROKU_STAGING_API_KEY` - Heroku API key used to deploy staging app,
 2. `HEROKU_PRODUCTION_API_KEY` - Heroku API key used to deploy production app.
 
-### Storing API keys
-In GitLab CI 7.12 a new feature was introduced: Secure Variables.
-Secure Variables can added by going to `Project > Variables > Add Variable`. 
-**This feature requires `gitlab-runner` with version equal or greater than 0.4.0.**
-The variables that are defined in the project settings are sent along with the build script to the runner.
-The secure variables are stored out of the repository. Never store secrets in your projects' .gitlab-ci.yml.
-It is also important that secret's value is hidden in the job log.
+## Storing API keys
+
+Secure Variables can added by going to your project's
+**Settings ➔ CI/CD Pipelines ➔ Secret variables**. The variables that are defined
+in the project settings are sent along with the build script to the Runner.
+The secure variables are stored out of the repository. Never store secrets in
+your project's `.gitlab-ci.yml`. It is also important that the secret's value
+is hidden in the job log.
+
+You access added variable by prefixing it's name with `$` (on non-Windows runners)
+or `%` (for Windows Batch runners):
 
-You access added variable by prefixing it's name with `$` (on non-Windows runners) or `%` (for Windows Batch runners):
 1. `$SECRET_VARIABLE` - use it for non-Windows runners
 2. `%SECRET_VARIABLE%` - use it for Windows Batch runners
+
+Read more about the [CI variables](../../variables/README.md).