SODE V1.7.1: Support for GSX controlling jetways for AI traffic

Besides fixing some minor bugs, this release mainly incorporates the necessary code modifications to have GSX control their SODE-based jetways in order to dock/undock to/from AI traffic. Of course, GSX needs to be updated as well for this to work, and the update from their part will be available very soon.

Small change log this time: changelog.