Have you checked out the deploy API yet?
To answer your other questions: you can in fact deploy straight from the modeler.
It's maybe also interesting to know that you can push your project directory (the directory which contains the mpr file) to Cloud Foundry using the command line, where it will be automatically built. It runs mxbuild.exe in the compile step in Cloud Foundry. Not officially supported for now, but we use it internally.
You can also have a look at the Build API You could build a package using that api and retrieve it to deploy it on your own environments. You could also have a look at mxbuild.exe which is part of the Modeler (Mendix\6.4.0\modeler) if you are on windows. You do have to stick al those together. though the building blocks are there.
The following MxForum thread has some more pointers to documentation about setting up CI in our own environment: