Updating README.md with some information about services with global endpoints.
Merge branch 'hotfix-0.5.1' into develop
Import httplib via six.moves.http_client

For python 3 compatibility.

Closes #46.
Adding support for parameter files from local files and from http(s) sources.
Forgot to add data file needed by test.
Allow paramfile check to be bypassed if param has a no_paramfile attribute.
Updating README and bumping version number.