Upgrade gems versions and add chefspec

also set kitchen related gems into integration group
Update Berksfile with new Chef API
Add integration test for ubuntu-14.04
Remove useless apt dependency
Upgrade ark version dependency
Use metadata to handle cookbook dependencies
Add missing ostruct require
Add package g++ for gperftools
Update autoconf_opts for readline with 14.04
Remove ssl warn message during integration tests
Add apt recipe for apt-get update
Fix autoconf_opts for readline library
Add more integration tests
Add spec helper and .rspec
Add custom matchers for ark
Fix directory name
Fix data_bag_item retrieving process
Add specs for default and rubies recipes
Add Travis CI support
Update README