[PATCH 25/27] qemu-img: implement short --help, remove global help() function

now once all individual subcommands has --help support, remove the large unreadable help() thing and replace it with small global --help, which refers to individual command --help for more info. While at it, also line-wrap list of formats after 75 chars. Since missing_argument() and unrecognized_

[PATCH 25/27] qemu-img: implement short --help, remove global help() function

now once all individual subcommands has --help support, remove the large unreadable help() thing and replace it with small global --help, which refers to individual command --help for more info. While at it, also line-wrap list of formats after 75 chars. Since missing_argument() and unrecognized_