Fix missing translation for non existent CWD [GH-1947]

lib/vagrant/environment.rb

@@ -74,7 +74,9 @@ module Vagrant
       opts[:cwd] ||= ENV["VAGRANT_CWD"] if ENV.has_key?("VAGRANT_CWD")
       opts[:cwd] ||= Dir.pwd
       opts[:cwd] = Pathname.new(opts[:cwd])
-      raise Errors::EnvironmentNonExistentCWD if !opts[:cwd].directory?
+      if !opts[:cwd].directory?
+        raise Errors::EnvironmentNonExistentCWD, cwd: opts[:cwd].to_s
+      end
 
       # Set the default ui class
       opts[:ui_class] ||= UI::Silent

templates/locales/en.yml

@@ -233,6 +233,11 @@ en:
         may run at any given time to avoid problems with VirtualBox inconsistencies
         occurring. Please wait for the other instance of Vagrant to end and then
         try again.
+      environment_non_existent_cwd: |-
+        The working directory for Vagrant doesn't exist! This is the
+        specified working directory:
+
+        %{cwd}
       forward_port_adapter_not_found: |-
         The adapter to attach a forwarded port to was not found. Please
         verify that the given adapter is setup on the machine as a NAT