Implement touch controls, improve button mapping

[rsn8887]

This PR does the following:

• implement direct touch controls (tap to click etc.)
• improve event code so it doesn't call PressKEY etc directly anymore, but generates proper DVL events. Will help in upstreaming later.
• change mapping to more closely reflect PS1 mapping (A for spell selection, L/R for char/inv left/right panels). On PS1 the same button (O) was also used for spell select.
• Map A button to cancel in menu, B button is OK in menu
• Support physical USB keyboards
• Make it clear in the README.MD to hold R over an installed game to launch Diablo, not album (otherwise touch keyboard doesn't work)
• Ensure touch keyboard fails gracefully without soft lock in case of low memory
• Allow skipping of intro Diablo logo with any controller button
• Use SDL Game Controller for input wherever possible (exactly the same functionality as before, but more portable)
• Refactor controller code to shorten switch statements
• Allow B button (in addition to Plus) to skip intro
• Prevent walking with dpad while talking to someone

[rsn8887]

Ready to merge @lantus (note the updated readme.md, it now specifically says to hold R over game and not use album to launch Diablo, to make the keyboard work, same as in @erfg12 latest PR).

[rsn8887]

It seems this PR already fixes the issues from PR #23 . So that one might not be needed anymore.

[erfg12]

Doesn't compile: ``c:/devkitpro/devkita64/bin/../lib/gcc/aarch64-none-elf/8.3.0/../../../../aarch64-none-elf/bin/ld.exe: obj/misc_msg.o: in functiondvl::PeekMessageA(dvl::tagMSG, void, unsigned int, unsigned int, unsigned int)': misc_msg.cpp:(.text+0x2c4): undefined reference to `switch_finish_simulated_mouse_clicks(int, int)' collect2.exe: error: ld returned 1 exit status make: *** [makefile:96: release/diablo-nx.elf] Error 1

[lantus]

does not build for me, please correct

[rsn8887]

One sec. I can fix this.

[rsn8887]

Ok I think I fixed it all. Sorry for the confusion :)

[rsn8887]

Ready to merge @lantus @erfg12 thank you for your patience :)

[lantus]

testing, then will merge shortly

[rsn8887]

Awesome!

[rsn8887]

I improved the code even more:

• Allow skipping of intro Diablo logo with any controller button
• Use SDL Game Controller for input wherever possible (exactly the same functionality as before, but more portable)
• Refactor controller code to shorten switch statements

[rsn8887]

• Allow both B button and Plus to skip intro

[rsn8887]

I am done for now. The improvements in here should warrant an official release after this PR is merged.

[rsn8887]

Just did one more:

• Prevent walking with dpad while talking to someone

[rsn8887]

But that's it.

[rsn8887]

Ready to merge.