Merge pull request #61 from bcwaldon/corectl-ssh

SSH around in corectl when necessary
feat(docs): refactor readme into docs folder
Merge pull request #62 from robszumski/master

feat(docs): break out readme into docs folder
fix(docs): fix incorrect link to config sample
Merge pull request #63 from robszumski/master

fix(docs): fix incorrect link to config sample
feat(corectl): Publish machine IP in list-machines cmd
Merge pull request #64 from bcwaldon/publish-machine-ip

feat(corectl): Publish machine IP in list-machines cmd
refactor(payload): Simplify JobPayload

* JobPayload is now just a Name and Unit
* Break the SystemdUnitFile data object into its own package
* Move code out of unit package to systemd package that interacts with systemd
feat(job): Implement new Job flow

* Jobs are now submitted, started, stopped, then destroyed
* Lots of refactoring internally to simplify Registry calls
* Drop unused events EventJobStatePublished, EventJobStateExpired
* Rename EventJobCancelled to EventJobStopped
Merge pull request #66 from bcwaldon/corectl-verbage

Implement new Job flow
feat(docs): add short service discovery doc
Merge pull request #65 from robszumski/master

feat(docs): add short service discovery doc
doc(corectl): Expand docs on corectl
Merge pull request #67 from bcwaldon/docs

doc(corectl): Expand docs on corectl
doc(corectl): Update command usage
fix(corectl): drop accidental log statement
doc(corectl): Complete documentation of corectl commands
Merge pull request #68 from bcwaldon/docs

moar corectl docs
refactor(ssh): Move ssh code to new pkg; prettify
feat(corectl): Implement ssh command