Add short flag counterparts

[Neved4]

Short flags enhance brevity and conciseness. Currently, some options lack equivalent short flags to invoke them:

• [X] -w, --warmup
• [X] -m, --min-runs
• [X] -M, --max-runs
• [X] -r, --runs
• [X] -s, --setup
• [X] -p, --prepare
• [X] -c, --cleanup
• [X] -P, --parameter-scan
• [X] -D, --parameter-step-size
• [X] -L, --parameter-list
• [X] -S, --shell
• [X] -N, (alias for '--shell=none')
• [X] -i, --ignore-failure
• [ ] -l, --style
• [ ] -t, --sort
• [X] -u, --time-unit
• [ ] -d, --show-output
• [ ] -O, --output
• [ ] -I, --input
• [X] -n, --command-name
• [X] -h, --help
• [X] -V, --version

Since --export variants lend themselves to further discussion they are tracked in https://github.com/sharkdp/hyperfine/issues/691