dont add hidden and bundler files to gem

sinatra-contrib/Rakefile

@@ -30,7 +30,7 @@ task 'sinatra-contrib.gemspec' do
   fields = {
     :authors => `git shortlog -sn`.scan(/[^\d\s].*/),
     :email   => `git shortlog -sne`.scan(/[^<]+@[^>]+/),
-    :files   => `git ls-files`.split("\n")
+    :files   => `git ls-files`.split("\n").reject { |f| f =~ /^(\.|Gemfile)/ }
   }
 
   fields.each do |field, values|

sinatra-contrib/sinatra-contrib.gemspec

@@ -25,9 +25,6 @@ Gem::Specification.new do |s|
 
   # generated from git ls-files
   s.files = [
-    ".gitignore",
-    "Gemfile",
-    "Gemfile.lock",
     "LICENSE",
     "README.md",
     "Rakefile",