Improved Recording features

[pilotnbr1]

The project could benefit from improved and mature recording features. It is openHD after all so should be all about image and image quality.

1. in qopenhd an actual "rec" button/control. This should be configurable between -screen recording of the current display -recording the recieved video stream only -recording the onboard (higher quality) video on the airpi -perhaps an option to do all of the above simultaneously
2. screenshot "stills"
3. record features should be possible to trigger via controller/transmitter
4. video storage space remaining
5. perhaps quality/resolution of the airpi recording
6. wishlist item (1) share to youtube. which will also promote project
7. wishlist item (2) live stream
8. wishlist item (3) airpi recording to external usb drive.. probably not used much as I think most people fly a pi zero or 3a+