Insert mode does not correctly work for OS X about github-markdown-toc

[ethanbond]

Hi @col-panic, I'm not qualified to be making a PR for this (you don't want me messing with things that delete files...) but in case you're blocked, here are some changes that I made that solve this.

From line 109:

    else
        local toc=`gh_toc_md2html "$gh_src" | gh_toc_grab "$gh_src_copy"`
        echo "$toc"
        if [ "$need_replace" = "yes" ]; then
            local ts="<\!--ts-->"
            local te="<\!--te-->"
            local dt=`date +'%F_%H%M%S'`
            local ext=".orig.${dt}"
            local toc_path="${gh_src}.toc.${dt}"
            local toc_footer="<!-- Added by: `whoami`, at: `date` -->"
            # http://fahdshariff.blogspot.ru/2012/12/sed-mutli-line-replacement-between-two.html
            # clear old TOC
            local comm="/${ts}/,/${te}/{//!d;}"
            sed -i${ext} "$comm" "$gh_src"
            # create toc file
            echo "${toc}" > "${toc_path}"
            echo -e "\n${toc_footer}\n" >> "$toc_path"
            # insert toc file
            sed -i "" "/${ts}/r ${toc_path}" "$gh_src"
            echo
            echo "!! TOC was added into: '$gh_src'"
            # echo "!! Origin version of the file: '${gh_src}${ext}'"
            # echo "!! TOC added into a separate file: '${toc_path}'"
            rm "$gh_src$ext"
            rm "$toc_path"
            echo
        fi

Note that I'm removing the generated .orig and .toc files. You may not want to do that.

The relevant changes are:

1. L121-ish: Adding a semicolon after the {//d} to {//d;} per https://stackoverflow.com/questions/6287755/using-sed-to-delete-all-lines-between-two-matching-patterns
2. L118: Removing the date formatting to just date
3. L127-ish: Adding an empty param "" per https://stackoverflow.com/questions/16745988/sed-command-with-i-option-in-place-editing-works-fine-on-ubuntu-but-not-mac

Hope this helps!

[col-panic]

Thanks a lot guys, and thanks for your effort @ethanbond 👍