Make sure that IThorSimpleStream sets bad bit if user tries to use dropped data
If a connection fails to set up correctly then mark the stream bad.

    This is similar to the behavior of standard streams.
    ie. Don't throw an exception but don't let the stream be used.
Add option to IThorSimpleStream to download all content.

    This allows a header only version of the library that always works.
    At the cost that it pre-downloads the whole content during construction.
Updated the READ ME