Update Rakefile

Author: kinnell

Rakefile

@@ -1,8 +1,20 @@
 # frozen_string_literal: true
 
 require 'bundler/gem_tasks'
-require 'rspec/core/rake_task'
 
-RSpec::Core::RakeTask.new(:spec)
+task default: :test
 
-task default: :spec
+desc 'Run tests'
+task :test do
+  exec 'bundle exec rspec'
+end
+
+desc 'Run ruby linter'
+task :lint do
+  exec 'bundle exec rubocop'
+end
+
+desc 'Enter Guard session'
+task :guard do
+  exec 'bundle exec guard'
+end