Porting to Aravis 0.8

Aravis 0.8 has seen a major rewrite of how communication errors are handled. Instead of relying on a status API, each function that can fail has an additional error parameter now. This is the standard way of handling error in the glib ecosytem. The nice side effect is now errors throw exceptions in bindings where the language support them (rust, python, javascript).

A quick port from the older series to 0.8 series is just a matter of adding a NULL parameter to most of the modified functions. But you are advised to take this opportunity to correctly handle errors.

There is a page explaining Glib errors and how to manage them in the Glib documentation.

During the camera configuration, in C language it can be somehow cumbersome to check for errors at each function call. A convenient way to deal with this issue is the following construction:

GError **error = NULL;

if (!error) arv_camera_... (..., &error);
if (!error) arv_camera_... (..., &error);
if (!error) arv_camera_... (..., &error);
if (!error) arv_camera_... (..., &error);

if (error) {
    handle error here;
    g_clear_error (&error);
}