added select_system_proxy module

repo/common/proxy.rc.local

@@ -0,0 +1,16 @@
+apt_proxy=/etc/apt/apt.conf.d/00proxy
+proxy_line=$(cat $apt_proxy | awk '{print $2}')
+proxy_srv=$(echo $proxy_line | cut -d'/' -f 3 | cut -d':' -f 1)
+
+echo "Le serveur proxy est : $proxy_srv"
+ping -c1 $proxy_srv &>/dev/null
+errout=$?
+if [[ $errout -eq 0 ]]; then
+    echo "Proxy fonctionnel ($errout)"
+    sed -i -e "s/^#Acquire:/Acquire:/" $apt_proxy
+    export http_proxy=$proxy_line
+    export https_proxy=$proxy_line
+else
+    echo "Pas de proxy ($errout)"
+    sed -i -e "s/^Acquire:/#Acquire:/" $apt_proxy
+fi