added help to cli

[kamysheblid]

This is what it looks like

$ lem --help
Usage: lem [ OPTION-OR-FILENAME ] ...
Options:
        -q, --no-init-file      do not load ~/.lem/init.lisp
        --slime PORT            start slime on PORT
        --eval EXPR             evaluate lisp expression EXPR
        --debug                 enable debugger
        --log-filename FILENAME file name of the log file
        --kill                  immediately exit
        -v, --version           print the version number and exit
        -h, --help              display this help and exit

[Sasanidas]

Oh, thanks for the contributions, it does indeed look really good 👍

[cxxxr]

Thank you so much!