Don't include test files in the gem package

Author: amatsuda

redcarpet.gemspec

@@ -42,21 +42,6 @@ Gem::Specification.new do |s|
     lib/redcarpet/render_man.rb
     lib/redcarpet/render_strip.rb
     redcarpet.gemspec
-    test/benchmark.rb
-    test/custom_render_test.rb
-    test/fixtures/benchmark.md
-    test/html5_test.rb
-    test/html_render_test.rb
-    test/html_toc_render_test.rb
-    test/markdown_test.rb
-    test/pathological_inputs_test.rb
-    test/redcarpet_bin_test.rb
-    test/redcarpet_compat_test.rb
-    test/safe_render_test.rb
-    test/smarty_html_test.rb
-    test/smarty_pants_test.rb
-    test/stripdown_render_test.rb
-    test/test_helper.rb
   ]
   # = MANIFEST =
   s.test_files = s.files.grep(%r{^test/})