Add basic pre-commit bash completion.

# vim: ft=bash

_pre_commit () {

    local cur prev words cword opts

    _init_completion || return

    opts='-h --help -V --version'

    commands='autoupdate clean gc init-templatedir install install-hooks migrate-config run sample-config try-repo uninstall validate-config validate-manifest help hook-impl'

    if [[ $cur == -* ]]

    then

        COMPREPLY=($(compgen -W "$opts" -- "$cur"))

    else

        COMPREPLY=($(compgen -W "$commands" -- "$cur"))

    fi

}

complete -F _pre_commit pre-commit