Add LCDDRVCE library

[calc84maniac]

Now you can do wacky LCD commands and stuff

I'd like some feedback on the API and docs, if possible. I consider the library implementation itself and its exported API to be more-or-less set in stone at this point, but the convenience macros can be changed as much as needed before merging.

I'm considering removing the bitfield-based raw parameter structs now that I've added parameter constants for most of the relevant commands. Though, that does bring to mind that we're missing a good way to define gamma parameters in C. Of course, that can be added later if needed.

[mateoconlechuga]

This looks good to me

[adriweb]

I've tried the two test programs on a few calcs:

• 82AEP (rev pre-A): both work fine
• 84+CET (rev A): both work fine
• 83PCE (rev A): both work fine
• 83PCE (rev E): both work fine
• 83PCE (rev L): both work fine
• 83PCEEP (rev M): half-res works, gradient "freezes" during the grey part at the top. Extremely rarely it works fully.
• 84+CEPy (rev S): [calc behaves as non-python] both work fine
• 84+CEPy (rev S, another): half-res works, gradient works 80% of the time (sometimes it freezes in the middle of random colors, sometimes there's some black area on top)
• 83PCEEP (rev O): half-res works, gradient "freezes" during the grey part at the top.
• 83PCEEP (rev S): half-res works, gradient "freezes" during the grey part at the top. Sometimes there's a vertical random-color bar. Extremely rarely it works fully.

Two other tests were submitted by other people, and they were working fine on non-python M+ calcs. So something python-related is interfering.

Here's the rev O "freezing" (I can still blindly press [clear] then turn the calc off then back on, though)

[adriweb]

(Marking as draft again because @calc84maniac was able to repro the python-related issue so he can investigate)