Add rubocop

Author: aetherknight

.rubocop.yml

@@ -0,0 +1,12 @@
+# The behavior of RuboCop can be controlled via the .rubocop.yml
+# configuration file. It makes it possible to enable/disable
+# certain cops (checks) and to alter their behavior if they accept
+# any parameters. The file can be placed either in your home
+# directory or in some project directory.
+#
+# RuboCop will start looking for the configuration file in the directory
+# where the inspected file is and continue its way up to the root directory.
+#
+# See https://docs.rubocop.org/rubocop/configuration
+Layout/LineLength:
+  Max: 120

recursive-open-struct.gemspec

@@ -40,6 +40,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency('rake', [">= 0"])
   s.add_development_dependency('rdoc', [">= 0"])
   s.add_development_dependency('rspec', "~> 3.2")
+  s.add_development_dependency('rubocop', ['>= 0'])
   s.add_development_dependency('simplecov', [">= 0"])
 
   s.add_dependency('ostruct')