RuboCop fixups

Also locks to the latest version of RuboCop so these sorts of random RuboCop
changes don't wind up in the middle of other PRs.

Gemfile

@@ -20,11 +20,11 @@ end
 group :test do
   gem "backports"
   gem "coveralls"
-  gem "simplecov",    ">= 0.9"
-  gem "json",         ">= 1.8.1"
-  gem "rspec",        "~> 3.0"
+  gem "simplecov", ">= 0.9"
+  gem "json",      ">= 1.8.1"
+  gem "rubocop",   "=  0.35.1"
+  gem "rspec",     "~> 3.0"
   gem "rspec-its"
-  gem "rubocop"
   gem "yardstick"
   gem "certificate_authority"
 end

lib/http/chainable.rb

@@ -83,7 +83,10 @@ def request(verb, uri, options = {})
     #   @option options [Float] :write Write timeout
     #   @option options [Float] :connect Connect timeout
     def timeout(klass, options = {})
-      klass, options = :per_operation, klass if klass.is_a? Hash
+      if klass.is_a? Hash
+        options = klass
+        klass   = :per_operation
+      end
 
       klass = case klass.to_sym
               when :null          then HTTP::Timeout::Null

lib/http/response/parser.rb

@@ -42,7 +42,8 @@ def on_body(chunk)
       end
 
       def chunk
-        chunk, @chunk = @chunk, nil
+        chunk  = @chunk
+        @chunk = nil
         chunk
       end