Read the README
Nest sub objects Parse/Validator
Remove unused `mappable`
update gemfile.lock
Revert "Remove unused `mappable`"

This reverts commit 8a0d803e2ce2ea1ecc9fe0440d2760eeda8a801f.
Merge branch 'master' of github.com:aq/csv2hash into aq-master

Conflicts:
	README.md
	lib/csv2hash/definition.rb
	lib/csv2hash/validator.rb
	spec/csv2hash/validator/mapping_spec.rb
FiX Conflict