Update gemspec.

Gemfile

@@ -8,6 +8,7 @@ gem 'ld-patch', github: "ruby-rdf/ld-patch",  branch: "develop"
 group :development, :test do
   gem 'ebnf',               github: "gkellogg/ebnf",                branch: "develop"
   gem 'json-ld',            github: "ruby-rdf/json-ld",             branch: "develop"
+  gem 'linkeddata',         github: "ruby-rdf/linkeddata",          branch: "develop"
   gem 'rdf-aggregate-repo', github: "ruby-rdf/rdf-aggregate-repo",  branch: "develop"
   gem 'rdf-isomorphic',     github: "ruby-rdf/rdf-isomorphic",      branch: "develop"
   gem 'rdf-reasoner',       github: "ruby-rdf/rdf-reasoner",        branch: "develop"

rdf-vocab.gemspec

@@ -11,7 +11,7 @@ Gem::Specification.new do |spec|
   spec.summary       = %q{A library of RDF vocabularies}
   spec.description   = %q{Defines several standard RDF vocabularies}
   spec.homepage      = "http://ruby-rdf.github.com/rdf-vocab"
-  spec.license       = "Public Domain" if spec.respond_to?(:license=)
+  spec.license       = "Unlicense"
 
   spec.platform      = Gem::Platform::RUBY
   spec.files         = %w(README.md LICENSE) + Dir.glob('lib/**/*.rb')
@@ -23,12 +23,12 @@ Gem::Specification.new do |spec|
 
   spec.add_runtime_dependency     "rdf",          '>= 2.0.0.beta', '< 3'
 
-  spec.add_development_dependency "ld-patch",     '>= 0.3', '< 1'
-  spec.add_development_dependency "rdf-reasoner", ">= 0.3"
+  spec.add_development_dependency "ld-patch",     '>= 0.3.0.beta', '< 1'
+  spec.add_development_dependency "rdf-reasoner", '>= 0.3.0.beta', '< 1'
   spec.add_development_dependency "bundler",      "~> 1.7"
   spec.add_development_dependency "rake",         "~> 10.0"
-  spec.add_development_dependency "rspec",        "~> 3.0"
-  spec.add_development_dependency "rspec-its",    "~> 1.0"
+  spec.add_development_dependency "rspec",        "~> 3.4"
+  spec.add_development_dependency "rspec-its",    "~> 1.2"
   spec.add_development_dependency "yard",         "~> 0.8"
 
   spec.extra_rdoc_files = %w(LICENSE README.md)