Deploying actions to package that doesn't exist fails.

[jthomas]

Actions can be deployed to an existing package (#87) but this requires the package to exist. If the package does not, the plugin doesn't create the package.

We should add support for auto-creating packages on deployment. Packages should also be removed if empty once resources are removed.

$ serverless deploy
Serverless: Packaging service...
Serverless: Excluding development dependencies...
Serverless: Compiling Functions...
Serverless: Compiling API Gateway definitions...
Serverless: Compiling Rules...
Serverless: Compiling Triggers & Feeds...
Serverless: Deploying Functions...

  Serverless Error ---------------------------------------

  Failed to deploy function (blahlahblah/hello) due to error: PUT https://openwhisk.ng.bluemix.net/api/v1/namespaces/_/actions/blahlahblah/hello?overwrite=true Returned
 HTTP 404 (Not Found) --> "The requested resource does not exist."

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  Your Environment Information -----------------------------
     OS:                     darwin
     Node Version:           9.3.0
     Serverless Version:     1.26.0