httperror class for collecting and transporting information about an
error.
We'll be handling exceptions within the controller layer, so exceptions
will not be thrown in these locations.
Implementation of HttpException getting exception message text from an
HttpError object passed in as an argument to the constructor. The parent
constructor is then passed the message as usual.
Signed-off-by: Nigel Packer <packene@gmail.com>
Test server path variable.