added background with opacity to QR-Code and card; bug in card opacity

examples/background-color-example.tex

@@ -0,0 +1,18 @@
+% !TeX program = xelatex
+\documentclass{businesscard-qrcode}
+
+\type{home}
+\givennames{Anna}
+\familynames{Beispiel}
+\street{Musterweg\ 7}
+\city{Zürich}
+\zip{8000}
+\country{CH}
+\phone{+41 44 123 45 67}
+\email{anna@example.ch}
+\homepage{example.ch}
+\background{yellow!20}
+
+\begin{document}
+	\drawcard
+\end{document}

examples/background-image-example.tex

@@ -0,0 +1,19 @@
+% !TeX program = xelatex
+\documentclass[bgscale=1.2,bgopacity=0.3,qrbgopacity=0.2
+]{businesscard-qrcode}
+
+\type{home}
+\givennames{Petra}
+\familynames{Test}
+\street{Bildstrasse\ 99}
+\city{Basel}
+\zip{4000}
+\country{CH}
+\phone{+41 61 123 45 67}
+\email{petra@example.ch}
+\background{background.png}
+\photo{photo.png}
+
+\begin{document}
+	\drawcard
+\end{document}

examples/photo-in-qr-example.tex

@@ -1,5 +1,5 @@
 % !TeX program = xelatex
-\documentclass[photoinqr,qrlogoscale=40,qreclevel=H]{businesscard-qrcode}
+\documentclass[photoinqr,qrlogoscale=0.4,qreclevel=H]{businesscard-qrcode}
 
 \type{home}
 \givennames{Lisa\ Linda}
@@ -12,7 +12,7 @@
 \phone{+1 234 567 8900}
 \email{ldoe@example.com}
 \homepage{example.com}
-\photo{photo.png}
+%\photo{photo.png} % uncomment if photo.png exists
 
 \begin{document}
 	\drawcard

examples/photo-large-example.tex

@@ -0,0 +1,19 @@
+% !TeX program = xelatex
+% Note: Requires photo.png in same directory
+\documentclass[photoscale=4]{businesscard-qrcode}
+
+\type{home}
+\givennames{Max}
+\familynames{Muster}
+\additionalnames{Big\ Photo\ Example}
+\street{Beispielstrasse\ 42}
+\city{Winterthur}
+\zip{8400}
+\country{CH}
+\phone{+41 52 123 45 67}
+\email{max@example.ch}
+\photo{photo.png}
+
+\begin{document}
+	\drawcard
+\end{document}