Initial release

This is the first release of apple-search-ads-go. It may be a little rocky, so I'm flagging it as a pre-release. The APIs I've tested work well so far, but you know how basing an entire program on the face-value documentation of another company can be. I will field any inconsistencies or improvements necessary to get this package up to the point it needs to be to use, but I'm otherwise comfortable enough with the fundamentals of this package to create the first release.