Implement file logging to fat:/ntrboot/ntrboot.log about ntrboot_flasher_nds HOT 2 CLOSED

this seems to be the final thing before release!

from ntrboot_flasher_nds.

Here's the theory for the code:

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The basic principle is that we have this vector that will contain nothing but std::string in it

We will write our logMessage so that upon each call, the vector is expanded by one, and the string sent to this function (logMessage), is parsed
from const char* to std::string and then stored in our vector (which was expanded previously to fit this)

In the end of all this, we must write our entire vector to ntrboot.log, and we can achieve this by writing a new function called writeBufferLog()
which is called immediately after a flashcart_core function call from menu.cpp (either cart->initialize, InjectFIRM or DumpFlash)

logMessage is called, I don't even know how many times, and with each call, a new line is created as well

So, every time we call a flashcart_core function (3 times in total: cart->initialize, InjectFIRM and DumpFlash), we will
immediately follow it by writeBufferLog()

The hardest part of all this is figuring out how va_list works. I must learn how to grab all the unknown number of parameters,
and combine them together in one solid packaged std::string to give to std::vector.

This may or may not work. The trickiest parts are string formatting (%d, %s and all that) everything properly to our std::string
by using asprintf()

from ntrboot_flasher_nds.