iFixit has completed its teardown of the second-generation Apple TV, and has already revealed several previously unknown details of the device. Notably, the second-generation Apple TV sports 8GB of internal flash storage, less than any other currently available iOS device save for the $99 iPhone 3GS, and also features 256MB of RAM, the same as the fourth-generation iPod touch and the iPad. Its Apple A4 chip bears the same marking as the one found…