update hanami-router version to v2

Author: github username

litestack.gemspec

@@ -33,7 +33,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency "sqlite3"
   spec.add_dependency "oj"
   spec.add_dependency "rack"
-  spec.add_dependency "hanami-router"
+  spec.add_dependency "hanami-router", "~> 2.0"
   spec.add_dependency "tilt"
   spec.add_dependency "erubi"