[Feature Request] Have 3DS autosleep

[The0zymandias]

A toggleable option in Rosalina that allows the 3ds to automatically go to sleep. This is primarily useful when downloading large updates from CTGP-7 or Universal-Updater, and is generally a good battery saving technique.

The basic idea is that the 3ds will automatically put itself in sleep mode depending on the configuration options of the user. These options include how long it has been since the user his provided input (via circle pad or buttom), whether to fall asleep only on the home menu or in game (also an option to allow/disallow sleep when a game is suspended), and whether to suspend sleep when downloading or uploading data over Wi-Fi.

Also, I'd like to note that updating the Luma3DS wiki to note features such as the message that can be displayed on the bottom of the pin screen would be great.