Remove Parser#reset and PullParser#reset

spec/oga/xml/pull_parser/general_spec.rb

@@ -11,11 +11,5 @@ describe Oga::XML::PullParser do
         @parser.node.is_a?(Oga::XML::Element).should == true
       end
     end
-
-    it 'resets the current node after parsing' do
-      @parser.parse { }
-
-      @parser.node.nil?.should == true
-    end
   end
 end