Stenographer WIP
Merge branch 'cops' into stenographer

Conflicts:
	lib/pacto/core/configuration.rb
	lib/pacto/core/validation_registry.rb
	spec/unit/pacto/validation_registry_spec.rb
Stenographer whose log is replayable via Pacto::Consumer; use Pacto::Consumer replay instead of contract.execute
Make stenographer log file configurable
Do nothing if stenographer log file is nil
ContractList -> ContractSet
Require name (or file), not file
Working on new documentation for the next release
Update README.md
Update README.md
Working on new documentation for the next release
Update README.md
Merged master
README links and README as default doc for viewdocs
Clerks sample
Added example file for custom clerk.
Merge branch 'v0.4.0_docs' of github.com:thoughtworks/pacto into v0.4.0_docs
Merge remote-tracking branch 'origin/stenographer' into v0.4.0_docs
Updated configuration sample/doc
Updated samples/docs for cops