[RFC] adding --raw option for screenshots and adding generic plugins for png and bmp - #124

Request For Comments

It's kinda two things in same PR but i could not test one without the other, so together they go.

1. Added --raw option for screenshots just like scpi and benchmark already has.

• had to modify all plugins and screenshots and gui as i needed to propagate port and protocol everywhere
• would like to add --port too, but screenshots already has -p used up for --plugin and I would like consistency with other commands. maybe give plugin some other short arg like -d / --device ?

2. Added generic screenshot plugins for png and bmp. let me know if you want other keywords or command.

• .regex = "lxi-tools/bmp" and .regex = "lxi-tools/png"
• command = "display:data? BMP\n"; and command = "display:data? PNG\n";

3. Testing

• new generic plugins works
• rigol-1000z and siglent-sdg still works too
• could not test gui as i have no machine to run it, but it compiles with no errors and no extra warnings as far as i can tell.

this would solve #122 and #123