Move to Ruby 2.4 for building Linux binaries

Author: ignisf

release/x86-linux/Vagrantfile

@@ -78,8 +78,8 @@ Vagrant.configure(2) do |config|
     sudo apt-add-repository ppa:brightbox/ruby-ng
     sudo apt-get update
     sudo apt-get dist-upgrade -y
-    sudo apt-get install -y build-essential git ruby-switch ruby2.3 ruby2.3-dev libglib2.0-dev
-    sudo ruby-switch --set ruby2.3
+    sudo apt-get install -y build-essential git ruby-switch ruby2.4 ruby2.4-dev libglib2.0-dev
+    sudo ruby-switch --set ruby2.4
     sudo gem install bundler
   SHELL
 end

release/x86_64-linux/Vagrantfile

@@ -78,8 +78,8 @@ Vagrant.configure(2) do |config|
     sudo apt-add-repository ppa:brightbox/ruby-ng
     sudo apt-get update
     sudo apt-get dist-upgrade -y
-    sudo apt-get install -y build-essential git ruby-switch ruby2.3 ruby2.3-dev libglib2.0-dev
-    sudo ruby-switch --set ruby2.3
+    sudo apt-get install -y build-essential git ruby-switch ruby2.4 ruby2.4-dev libglib2.0-dev
+    sudo ruby-switch --set ruby2.4
     sudo gem install bundler
   SHELL
 end