Update dependency versions

Makefile

@@ -1,4 +1,4 @@
-.PHONY: release
+.PHONY: release gemspec_validate
 
 unexport LANG
 unexport LC_ADDRESS
@@ -17,7 +17,10 @@ unexport LC_TIME
 # NB:
 # VERSION does NOT include the v suffix
 
-release:
+gemspec_validate:
+	@rake gemspec
+
+release: gemspec_validate
 ifeq ($(VERSION),)
 	$(error VERSION must be set to build a release and deploy this package)
 endif

riak-client.gemspec

@@ -16,17 +16,17 @@ Gem::Specification.new do |gem|
 
   # Deps
   gem.add_development_dependency 'rspec', '~> 3.0'
-  gem.add_development_dependency 'rake', '~> 10.1.1'
-  gem.add_development_dependency 'yard', '~> 0.8.7'
+  gem.add_development_dependency 'rake', '~> 10.1'
+  gem.add_development_dependency 'yard', '~> 0.8'
   gem.add_development_dependency 'kramdown', '~> 1.4'
-  gem.add_development_dependency 'simplecov', '~> 0.10.0'
-  gem.add_development_dependency 'instrumentable', '~> 1.1.0'
+  gem.add_development_dependency 'simplecov', '~> 0.10'
+  gem.add_development_dependency 'instrumentable', '~> 1.1'
   gem.add_development_dependency 'rubocop', '~> 0.40'
 
-  gem.add_runtime_dependency 'i18n', '>=0.6.8'
+  gem.add_runtime_dependency 'i18n', '~> 0.6'
   gem.add_runtime_dependency 'beefcake', '~> 1.1'
-  gem.add_runtime_dependency 'multi_json', '~>1.0'
-  gem.add_runtime_dependency 'innertube', '~>1.0.2'
+  gem.add_runtime_dependency 'multi_json', '~> 1.0'
+  gem.add_runtime_dependency 'innertube', '~> 1.0'
   gem.add_runtime_dependency 'cert_validator', '~> 0.0.1'
 
   # Files