only include folders we care on gem file

memcached.gemspec

@@ -10,8 +10,8 @@ Gem::Specification.new do |s|
   s.summary = "An interface to the libmemcached C client."
   s.homepage = "http://evan.github.com/evan/memcached/"
 
-  s.files         = `git ls-files`.split("\n")
-  s.test_files    = `git ls-files -- {test,spec,features}/*`.split("\n")
+  s.files         = `git ls-files -- {lib,ext,vendor}/*`.split("\n") + %w(LICENSE README.md CHANGELOG)
+  s.test_files    = `git ls-files -- {test}/*`.split("\n")
   s.require_paths = ["lib", "ext"]
   s.extensions = ["ext/memcached/extconf.rb"]