When we initialize the reader, we currently tell only which type of
interface we are using, but we do not print the reader number or the
device path.
Let's extend the messages so that the path is printed. To prevent
problems with integration-tests, let's also add an environment variable
that we can use to detect when pySim runs inside a integration-test.
Related: OS#6210
Change-Id: Ibe296d51885b1ef5f9c9ecaf1d28da52014dcc4b