bugfix: handle train errors in inspec execution

lib/inspec/cli.rb

@@ -140,8 +140,8 @@ class Inspec::InspecCLI < Inspec::BaseCLI # rubocop:disable Metrics/ClassLength
       jres = res.respond_to?(:to_json) ? res.to_json : JSON.dump(res)
       puts jres
     end
-  rescue RuntimeError => e
-    puts e.message
+  rescue RuntimeError, Train::UserError => e
+    $stderr.puts e.message
   end
 
   desc 'version', 'prints the version of this tool'

lib/utils/base_cli.rb

@@ -68,7 +68,7 @@ module Inspec
       runner = Inspec::Runner.new(o)
       targets.each { |target| runner.add_target(target, opts) }
       exit runner.run
-    rescue RuntimeError => e
+    rescue RuntimeError, Train::UserError => e
       $stderr.puts e.message
       exit 1
     end