Add jQuery Mobile 1.4.0-alpha.1

lib/development_tasks/jquery_mobile_rails_tasks.rake

@@ -9,17 +9,13 @@ task :"jquery_mobile_rails_css_fix" do
   Dir.glob(File.join(STYLESHEETS_PATH, "*.css")).each do |css_file_name|
     puts css_file_name
     file_content = ''
-    File.open(css_file_name, "r:UTF-8") do |file|
-      file_content = file.read
-    end
-    file_content.gsub! /url\(images\/([A-Za-z0-9_-]*\.)(png|gif)\)/ do
-      "image-url(\"jquery-mobile/#{$1}#{$2}\")"
-    end
+    file_content = File.read(css_file_name, mode: "r:UTF-8")
 
-    File.open(css_file_name, 'w') do |file|
-      file << file_content
+    file_content.gsub! /url\(images\/(.*\.)(png|gif)\)/ do
+      "image-url(\"jquery-mobile/#{$1}#{$2}\")"
     end
 
+    File.write(css_file_name, file_content)
     File.rename(css_file_name, "#{css_file_name}.scss")
   end