Create Procfile based on config selection

[mthomps4]

In index.ts "Heroku Setup"

There's a commented-out TODO to create a Procfile dynamically.
This seems to be ok, however, there are remaining issues with Heroku Setup. See #139

Confirm the file is created dynamically once other issues have been resolved and remove the template file.

[mthomps4]

Closing for #179