add .error(), .option() and Integration(settings)
.handle(): pass response to callback on error
.option(): preserve meta for tests
add .channels()
add .requires()
.requires(): add method filter
statics: typo
.option(): fix custom validator
proto: remove .requires() and .option() for .ensure()
validations: use object instead of array
.ensure(): make sure the path is set correctly
validations: move to array
proto: remove all settings
.ensure(): error if setting is an empty string
deps: upgrade facade
add .reject() & use reject() in .ensure()
Merge pull request #25 from segmentio/refactor

Refactor