qrcode: display qrcode on main page

Relies on libqrencode, cloned and compiled by cmake

Tuleap: #616
Change-Id: I2cb9281289478321751a947fc8828bf0ba5c6f27
diff --git a/.gitmodules b/.gitmodules
index 1db2f94..31602d4 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,6 @@
 [submodule "sparkle/Sparkle"]
 	path = sparkle/Sparkle
 	url = https://github.com/sparkle-project/Sparkle.git
+[submodule "libqrencode"]
+	path = libqrencode
+	url = https://github.com/fukuchi/libqrencode.git