Screenshot hotkey and JPEG output

[qwr]

The /screenshot console command is nice. But what many games have is a dedicated screenshot key, perhaps PrtScn, so I don't have to open the console and scroll up to retype the command.

In addition, the output format is only PNG. On my screen, each screenshot comes out to 7 MB. The textures in game do not compress losslessly well and I do not need every pixel of rust and dirt to be perfect, so a JPEG output with quality parameter could easily be 1/10 or 1/20 the storage.