Casio fx-CG series port (#324)

* Initial test - working on Linux

* Try to make it work with liba

* Stop using liba and the filesystem

* IT WORKS

* Key input, full res, fix some of the crashes

* Fix the hang when doing calculations

* Add some more key mappings

* Fix the square root issue

* Icons

* Better key mappings, brightness control, better gamma correction, more effficient framebuffer

* Cleanup stage 1

* Cleanup stage 2

* Make the build system build a g3a

* Make it not exit when you press the menu button

* Add Casio port to README

* Use omega-master instead of omega-dev

* Fix mistake with cherry-picking in the README

* Fix internal storage crash

* Fix compile error on Numworks calculators

* Upsilon branding

* Sharper icon

* Make the CI work

* Add power off and improve menu

* Map Alpha + up/down to the brightness shortcut

* Add missing file

* Fix web CI build

* Revert "Fix web CI build"

This reverts commit f19657d9fc.

* Change "prizm" to "fxcg"

* Add FASTLOAD option for Add-in Push

* Add some charatcers to the catalog on Casio and improve key mappings

* Build with -Os -flto

* Disable LTO for now as it's causing crashes

* Put back the fonts I accidently changed

I'd like to add an option for this though as I prefer the ones from Epsilon

Makefile

@@ -93,6 +93,7 @@ help:
 	@echo "  make PLATFORM=simulator TARGET=web"
 	@echo "  make PLATFORM=simulator TARGET=windows"
 	@echo "  make PLATFORM=simulator TARGET=3ds"
+	@echo "  make PLATFORM=simulator TARGET=fxcg"
 
 .PHONY: doc
 doc:
@@ -127,6 +128,7 @@ ifndef USE_LIBA
 endif
 ifeq ($(USE_LIBA),0)
 include liba/Makefile.bridge
+include libaxx/Makefile.bridge
 else
 SFLAGS += -ffreestanding -nostdinc -nostdlib
 include liba/Makefile