specify versions for rake, rack-test, and coveralls

Author: Jim Cushing

tilt-handlebars.gemspec

@@ -23,9 +23,9 @@ Gem::Specification.new do |spec|
   spec.add_dependency "handlebars", "~> 0.7"
 
   spec.add_development_dependency "bundler", "~> 1.3"
-  spec.add_development_dependency "rake"
+  spec.add_development_dependency "rake", "~> 10"
   spec.add_development_dependency "minitest", "~> 5.0"
   spec.add_development_dependency "sinatra", "~> 1.4"
-  spec.add_development_dependency "rack-test"
-  spec.add_development_dependency "coveralls"
+  spec.add_development_dependency "rack-test", "~> 0.6"
+  spec.add_development_dependency "coveralls", "~> 0.6"
 end