Make spotfire into a namespace package

[huwf-cloudcom]

Because the spotfire package has a __init__.py file, it is not a namespace package. This makes it difficult to import modules from spotfire in downstream packages which are using the same namespace.

A possible solution would be to use pkgutil in the file to extend the path as follows:

from pkgutil import extend_path
__path__ = extend_path(__path__, __name__)

This is obsolete, but I do not know of any other ways beyond removing the __init__.py and it is possible that other libraries have dependencies on the imports defined in that.