Allow mix.exs app name and nerves hub product name to be different

[LostKobrakai]

This comes up when signing and attempting to publish a firmware, where the nerves hub product doesn't match the firmware/mix app name:

NervesHub server: manage.nervescloud.com:443
NervesHub organization: kobrakai
NervesHub product: wip
------------
Organization: kobrakai
  product:      workflow
  version:      0.2.0
  platform:     rpi0
  architecture: arm
  uuid:         638b587e-80b2-5c13-332c-9b3055adf1b0

The latter "product" seems to be taken from the firmware metadata.

[jjcarstens]

I believe you can accomplish this in your firmware by using the :name key in your project/0 definition. That is preferred over :app when building the firmware

def project do
  app: :my_app,
  name: "My Product",
  ...
end