[Feature] Read in from stdin/pipe

I'm using the transfer.sh script linked on the website. Would it be possible to extend this script so that I can pipe input into it, rather than having to specify an existing file?

```
transfer(){ if [ $# -eq 0 ];then echo "No arguments specified.\nUsage:\n transfer \n ... | transfer ">&2;return 1;fi;if tty -s;then file="$1";file_name=$(basename "$file");if [ ! -e "$file" ];then echo "$file: No such file or directory">&2;return 1;fi;if [ -d "$file" ];then file_name="$file_name.zip" ,;(cd "$file"&&zip -r -q - .)|curl --progress-bar --upload-file "-" "https://transfer.sh/$file_name"|tee /dev/null,;else cat "$file"|curl --progress-bar --upload-file "-" "https://transfer.sh/$file_name"|tee /dev/null;fi;else file_name=$1;curl --progress-bar --upload-file "-" "https://transfer.sh/$file_name"|tee /dev/null;fi;}
```