Migrating a lightning configuration from one organization to another:

Hello.  I have built out in a trial org we have access to, an implementation of our application as a lightning app.  It includes the app definition, a ton of lightning page layouts, etc. etc.

Is there a way to use change sets to bring all the lightning related metadata from one organization to another?   We want to deploy this lightning version of our application to existing customers without going through the painstaking process of rebuilding all this manually?

I only have a bit of experience with change sets --- but would appreciate info on the following:

1)  How to move a change set from one organization into another  (I've used change sets from a sandbox to a production in the same org -- but never from one org to another.

2)  What are the lightning items (metadata) that I would add to the change set?  I want to migrate the lightning app itself, (with its tabs etc), as well as all the lightning page layouts associated with it.

Appreciate if anyone can point to me to relatively clear instructions on how to best handle this.  Thanks!