Add more robust program arguments support to capture

[bgottula]

Add more robust program options support to capture. I did a quick survey of available libraries and https://github.com/CLIUtils/CLI11 appears to be popular and uses modern C++. It is available as libcli11-dev on Ubuntu 22.04.

Use this as an opportunity to replace some of the hard-coded constants in the software with program args. Some to consider:

• SER output filename
• Camera name
• Preview window frame rate throttle
• Histogram window refresh rate
• Whether or not to start up with disk writing paused
• Initial gain and exposure time
• AGC enable at startup

Further work to do:

• Update CMake for capture to remove add_subdirectory(CLI11) and instead require CLI11 to be installed in the host system.

[bgottula]

I've done the work on branch cli11. As of now, in CMake CLI11 is added as a subdirectory.