Always use rvm system and also update webpack config (theforeman#599)

.gitignore

@@ -10,8 +10,6 @@ boxes.yaml
 scripts
 repo
 Gemfile.lock
-.ruby-version
-.ruby-gemset
 *.retry
 *.pyc
 user_playbooks

.ruby-version

@@ -0,0 +1 @@
+system

docs/development.md

@@ -243,9 +243,11 @@ To work with webpack-dev-server, ensure the following lines are in your `~/forem
 This will instruct Foreman to use Webpack from an https source. Now we need to make sure Webpack is using the right certificates to serve the development content through HTTPS. We're going to save these configuration values on `~/foreman/.env`:
 
 ```
-WEBPACK_OPTS='--https --key /etc/pki/katello/private/katello-default-ca.key --cert /etc/pki/katello/certs/katello-default-ca.crt --cacert /etc/pki/katello/certs/katello-default-ca.crt'
+WEBPACK_OPTS='--https --key /etc/pki/katello/private/katello-default-ca.key --cert /etc/pki/katello/certs/katello-default-ca.crt --cacert /etc/pki/katello/certs/katello-default-ca.crt --host 0.0.0.0 --public centos7-devel.example.com'
 ```
 
+Replace centos7-devel.example.com with the public hostname of your development server, if different.
+
 Remember to run `source ~/foreman/.env` before running your Webpack server, so that the right options to enable HTTPS are loaded.
 
 Additionally, Foreman uses [secureheaders](https://github.com/twitter/secureheaders) to protect users from different attacks. secureheaders will block requests to the webpack development server, as it's not running in localhost:3000. To allow it, change the following lines in `~/foreman/config/initializers/secure_headers.rb`, substituting centos7-devel.example.com for your fqdn, you can get this value by running `hostname -f`.