Checked for existing packages self-install-script (#1573)

* fixed yesno and silenced git clone

* Checked for existing packages instead of trying to install regardless

contrib/debian-ubuntu-install.sh

@@ -29,16 +29,19 @@ intip=$(ip r g 8.8.8.8 | awk 'NR==1{print $7};')
 # Installed whiptail for script prerequisite
 apt-get -qq install whiptail -y
 
+# Check to see what SickRage Dependencies are missing
+packages=$(dpkg -l unrar-free git-core openssl libssl-dev python2.7 2>1 | grep "no packages" | \
+           awk '{ print $6 }' | tr '\n' ' ')
+if [[ $packages ]]; then
 # Show Whiptail and install required files
     {
     i=1
     while read -r line; do
         i=$(( $i + 1 ))
         echo $i
-    done < <(apt-get update && apt-get install unrar-free git-core openssl libssl-dev python2.7 -y)
-} | whiptail --title "Progress" --gauge "
-   Installing unrar-free, git-core, openssl, libssl-dev, and python2.7" 8 80 0
-
+    done < <(apt-get update && apt-get install $packages -y)
+    } | whiptail --title "Progress" --gauge "Installing $packages" 8 80 0
+fi
 # Check to see if all prior packages were installed sucessfully. if not exit 1 and display whiptail issues
 
 if [[ $(dpkg -l unrar-free git-core openssl libssl-dev python2.7 2>&1 | grep "no packages" | \