sprockets upgrade

stop bundling all js files in dev, replace with turbo boosted serving of assets

lib/middleware/turbo_dev.rb

@@ -0,0 +1,21 @@
+module Middleware
+  # this class cheats and bypasses rails altogether if the client attme
+  class TurboDev
+    def initialize(app, settings={})
+      @app = app
+    end
+    def call(env)
+      # hack to bypass all middleware if serving assets, a lot faster 4.5 seconds -> 1.5 seconds
+      if (etag = env['HTTP_IF_NONE_MATCH']) && env['REQUEST_PATH'] =~ /^\/assets\//
+        name = $'
+        etag = etag.gsub "\"", ""
+        asset = Rails.application.assets.find_asset(name)
+        if asset && asset.digest == etag
+          return [304,{},[]]
+        end
+      end
+
+      @app.call(env)
+    end
+  end
+end