deps: update rubocop to version 0.60.0

Update rubocop to version 0.60.0 (#18)

.rubocop.yml

@@ -6,6 +6,9 @@ AllCops:
 Gemspec/OrderedDependencies:
   Enabled: false
 
+Layout/AlignHash:
+  Enabled: false
+
 Layout/EmptyLineAfterGuardClause:
   Enabled: false
 

dyndnsd.gemspec

@@ -31,5 +31,5 @@ Gem::Specification.new do |s|
   s.add_development_dependency 'rake'
   s.add_development_dependency 'rspec'
   s.add_development_dependency 'rack-test'
-  s.add_development_dependency 'rubocop', '~> 0.59.0'
+  s.add_development_dependency 'rubocop', '~> 0.60.0'
 end