FIX: 6to5 was renamed to Babel

I can't believe they just pulled the old gem and broke people deploying
our site to production. I get it, your name changed, but don't break
other people's apps with no deprecations.

lib/es6_module_transpiler/tilt/es6_module_transpiler_template.rb

@@ -1,7 +1,22 @@
 require 'execjs'
-require '6to5'
+require 'babel/transpiler'
 
 module Tilt
+
+  class Console
+    def initialize(prefix=nil)
+      @prefix = prefix || ''
+    end
+
+    def log(msg)
+      Rails.logger.info("#{@prefix}#{msg}")
+    end
+
+    def error(msg)
+      Rails.logger.error("#{@prefix}#{msg}")
+    end
+  end
+
   class ES6ModuleTranspilerTemplate < Tilt::Template
     self.default_mime_type = 'application/javascript'
 
@@ -15,7 +30,7 @@ module Tilt
 
     def self.create_new_context
       ctx = V8::Context.new(timeout: 5000)
-      ctx.eval("var self = this; #{File.read(ES6to5::Source.path)}")
+      ctx.eval("var self = this; #{File.read(Babel::Transpiler.script_path)}")
       ctx.eval("module = {}; exports = {};");
       ctx.load("#{Rails.root}/lib/es6_module_transpiler/support/es6-module-transpiler.js")
       ctx
@@ -64,6 +79,7 @@ module Tilt
 
       klass = self.class
       klass.protect do
+        klass.v8['console'] = Console.new("BABEL: #{scope.logical_path}: ")
         @output = klass.v8.eval(generate_source(scope))
       end
 
@@ -118,7 +134,7 @@ module Tilt
 
     def generate_source(scope)
       js_source = ::JSON.generate(data, quirks_mode: true)
-      js_source = "to5.transform(#{js_source}, {ast: false, whitelist: ['es6.constants', 'es6.properties.shorthand', 'es6.arrowFunctions', 'es6.blockScoping']})['code']"
+      js_source = "babel.transform(#{js_source}, {ast: false, whitelist: ['es6.constants', 'es6.properties.shorthand', 'es6.arrowFunctions', 'es6.blockScoping']})['code']"
       "new module.exports.Compiler(#{js_source}, '#{module_name(scope.root_path, scope.logical_path)}', #{compiler_options}).#{compiler_method}()"
     end