Fix a dependency loop

rspec and rspec-spies were creating a dependency loop when no versions
were specified. This also fixes an annoying warning on gem creation.

Author: ignisf

libv8.gemspec

@@ -28,8 +28,8 @@ Gem::Specification.new do |s|
   s.extensions = ["ext/libv8/extconf.rb"]
   s.require_paths = ["lib", "ext"]
 
-  s.add_development_dependency "rake"
-  s.add_development_dependency "rake-compiler"
-  s.add_development_dependency "rspec"
-  s.add_development_dependency "rspec-spies"
+  s.add_development_dependency 'rake', '~> 10'
+  s.add_development_dependency 'rake-compiler', '~> 0'
+  s.add_development_dependency 'rspec', '~> 2'
+  s.add_development_dependency 'rspec-spies', '~> 2'
 end