Add QR code flag to goshy

This commit adds an additional flag for displaying an QR code as the
respone of running goshy. It requires the qrencode package.

One could check if the depedency exists, but any OS should be able to
report this themselves. So this bloat was not added.

Sadly `qrencode -t ASCII` was not working for me. It printed a not
scannable QR code. Thus an image is opened.

contrib/bash/goshy

@@ -9,6 +9,7 @@ Options:
   -i --instance          Complete URL to the gosh instance.
   -p --period TIMEFRAME  Set a custom expiry period.
   -u --only-url          Print only URL as response.
+  -q --qr-code           Print only QR code as response.
 EOF
 }
 
@@ -37,6 +38,10 @@ while :; do
       ONLYURL="1"
       ;;
 
+    -q|--qr-code)
+      QRCODE="1"
+      ;;
+
     *)
       FILE=$1
       break
@@ -66,5 +71,7 @@ CURL_CMD="${CURL_CMD} ${GOSH_INSTANCE}"
 if [[ -n ${ONLYURL+x} ]]; then
   CURL_CMD="${CURL_CMD}/?onlyURL"
 fi
-
+if [[ -n ${QRCODE+x} ]]; then
+  CURL_CMD="${CURL_CMD}/?onlyURL -s | qrencode --size=15 -o - | xdg-open -"
+fi
 eval "$CURL_CMD"