fuse Merge Request #21: feat: General option (checkbox) to patch Didaktik 80 + Spectrum 128K (open)

Added general option to alter 128k's memory port decoder as per Didaktik M 128K HW patch to support Didaktik D40/D80. It requires also switching ROM to 1 = 48K rom.
Reset needed after changing value of this setting.

fix: Normalized a bit the hacky port writeback mechanism. Active for 128K and Plus 2.
fix: Rendering of & from options.dat inconsistent between platforms. Win32 needs &&, while unix not. So I replaced it with "and"

feat: Implement postcheck and posthook functions when saving general options. Implemented this for win32, widget and gtk version of options.pl.
feat: Added check for the first general option that when changed forces a hard reset.
feat: Fixed it by separating function for saving setting in menu Options/General

See more
https://sourceforge.net/p/arki55-fuse-mod/tickets/3/

[Arki55]

This is not the only possible way how to implement such patch.
In the linked ticket, within comment I have mentioned also other possible ways how I could (re)do this..
.. as a seprate peripheral (many peripherals have options done like that)
.. as additional machine Didaktik 128K