New "Submit System Data" function

[GerbilSoft]

The "Submit System Data" function allows users to submit console information to a central Wii U system database, which is publicly viewable here: https://wiiu.gerbilsoft.com/ (filtering and pagination functions to be added at a later date)

In particular, this will be used to try to correlate serial number batches to MLC manufacturers. If we can find a pattern, we can use that to estimate which consoles have Hynix eMMC without opening or haxing them.

Other changes:

• Split several functions out of menu.c and into their own files.
• Add a GitHub "link" to the main menu. (Not really a link, since you can't click it...)
• gfx_print(): Add GfxPrintFlag_Underline to automatically underline text (for links); handle newlines.
• System Information: Rearrange the non-mdinfo data into three columns; show the BSP revision.

The version number is now defined as a macro in menu.h.

[emukidid]

I have a bunch to submit when this gets merged :)

Couldn't help myself, submitted some of my consoles.