added external ColorPicker.dll
removed ChooseColor
get selection color moved out to separate function
put  selection color moved out to separate function
simplify logic and use external ColorPicker.dll in Windows
add paste argument to command (for example, to use as view.run_command('color_pick', False) for browsing colors without paste
use RGB instead of BGR in windows
remove unused custom color array functions
use string format instead of byte table to simplify code
readme: add link to the Visual Color Picker
readme: update Windows screenshot