[gem] Add optional Gemfile for installing puppet and friends

Gemfile

@@ -0,0 +1,8 @@
+source 'https://rubygems.org'
+
+gem 'puppet', '~> 3.7.2'
+gem 'hiera', '~> 1.3.4'
+gem 'hiera-puppet', '~> 1.0.0'
+gem 'r10k', '~> 1.1.4'
+
+# vim:ft=ruby

Gemfile.lock

@@ -0,0 +1,38 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    CFPropertyList (2.2.8)
+    colored (1.2)
+    cri (2.4.1)
+      colored (>= 1.2)
+    facter (2.4.6)
+      CFPropertyList (~> 2.2.6)
+    hiera (1.3.4)
+      json_pure
+    hiera-puppet (1.0.0)
+      hiera (~> 1.0)
+    json_pure (2.0.1)
+    log4r (1.1.10)
+    puppet (3.7.5)
+      facter (> 1.6, < 3)
+      hiera (~> 1.0)
+      json_pure
+    r10k (1.1.4)
+      colored (>= 1.2)
+      cri (~> 2.4.0)
+      json_pure
+      log4r (>= 1.1.10)
+      systemu (~> 2.5.2)
+    systemu (2.5.2)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  hiera (~> 1.3.4)
+  hiera-puppet (~> 1.0.0)
+  puppet (~> 3.7.2)
+  r10k (~> 1.1.4)
+
+BUNDLED WITH
+   1.12.5

README.md

@@ -12,12 +12,36 @@
   * `modules/ldn` contains the private stuff (ideally it should be hiera files
     only),
 
-## Basic usage
+## Installation
+
+### Prerequists
+
+* ssh (client)
+
+* git
+
+* Puppet stuff: puppet (3.7), hiera, r10k
+
+### Installing puppet with bundler
+
+You might want to install puppet using bundler in order to have the correct
+version (especially if your distribution does not ship the correct version):
+
+    apt install bundler
+    bundle install
+
+The local ruby/puppet commands must be executed with `bundle exec`:
+
+    bundle exec r10k puppetfile install Puppetfile
+
+### SSH
 
 This documentation assumes that your ~/.ssh/config is configured in order to
 access to the servers with `ssh $home.newldn` and the GIT repositories with
 `ssh gitldn`.
 
+## Basic usage
+
 Clone the repository:
 
     git clone gitldn:puppet/puppet