Make automatic helpers smarter. Fixes #510

middleman-core/fixtures/external-helpers/helpers/derp.rb

@@ -1,3 +1,3 @@
-module ThreeHelper
+module Derp
   def three; "Three"; end
 end

middleman-core/fixtures/external-helpers/helpers/four_helpers.rb

@@ -1,3 +1,3 @@
-module FourHelper
+module FourHelpers
   def four; "Four"; end
 end

middleman-core/fixtures/external-helpers/helpers/yet_another_thingy.rb

@@ -1,3 +1,3 @@
-module TwoHelper
+module YetAnotherThingy
   def two; "Two"; end
 end

middleman-core/lib/middleman-core/core_extensions/external_helpers.rb

@@ -10,7 +10,7 @@ module Middleman
         def registered(app)
           # Setup a default helpers paths
           app.set :helpers_dir, "helpers"
-          app.set :helpers_filename_glob, "**/*_helper.rb"
+          app.set :helpers_filename_glob, "**/*.rb"
           app.set :helpers_filename_to_module_name_proc, Proc.new { |filename|
             basename = File.basename(filename, File.extname(filename))
             basename.camelcase