Add module to your Drupal installation via ZenCI deploy

So you have your own repo with module code

1. You need to create a file to install module after deploy:
```
#!/bin/sh

echo "Installing module to $DOCROOT"

# Create modules dir.
mkdir -p $DOCROOT/sites/all/modules
cd $DOCROOT/sites/all/modules

#link module folder
ln -s $ZENCI_DEPLOY_DIR ./$ZENCI_REPO_NAME

#return to website root
cd $DOCROOT

#enable module
drush en -y $MODULENAME
```

If your module name is the same as repo name, you can replace $MODULENAME with $ZENCI_REPO_NAME

2. Enable Zen.ci for this repo
3. set .ssh/authorized_keys with 600 permission and write there a public_key for this repo.
4. Create .zenci.yml file
```
deploy:
  master:
    server: p1.zen.ci
    username: zen
    dir: '{home}/github/{repo_owner}/{repo_name}/{branch}'
    env_vars:
      docroot: '{home}/domains/zen.ci'
      domain: zen.ci
      modulename: billing_client
    scripts:
      init: '{home}/scripts/module_init.sh'
```
When you commit .zenci.yml - module will be uploaded and enabled.