Change travis rake task

lib/tasks/travis.rake

 task :travis do
-  ["spinach", "rspec spec"].each do |cmd|
+  ["rake spinach", "rake spec"].each do |cmd|
     puts "Starting to run #{cmd}..."
     system("export DISPLAY=:99.0 && bundle exec #{cmd}")
     raise "#{cmd} failed!" unless $?.exitstatus == 0