Add saving physical game controller key mappings to keys for each game

[Korb]

As I understand it, in ZXplorer the user can customize the mapping of all the keys of the controller (be it Xbox Controller, PlayStation Controller, Nintendo Switch, Generic Controller and Steam Controller) to the buttons used by the game running in the emulator.

Please consider saving these settings in a separate file.

And add automatic loading of the configuration file if the only file with mapping settings is found in the folder with the game file. Or, display a window for the user to select the settings file if several such files are found in the folder.

[Korb]

I realized my mistake. ZXplorer is only a file browser, with the ability to launch games using various third-party emulators. And it supports customization of running emulators as much as the command line keys of these emulators allow. No more and no less.