Unknow system -c install fix

unknown systems with apt-get were still attempting to install OpenCV 2.4.8 pre-packaged.
Ubuntu and Arch Linux now fully build FireSight and OpenCV 2.4.13 without any problems, aside from arch having unknown package manager. But the user is directed to manually install these required packages.

build

@@ -330,7 +330,7 @@ elif [[ "$(grep a22082 /proc/cpuinfo)" == *a22082* ]]; then
     echo -e "\n${GREEN}SUCCESS${NC}  : OPENCV 2.4 INSTALLED\n"
   fi
 
-elif [ "$(type -p apt-get)" = "" ]; then
+elif [ "$(type -p apt-get)" = "" ] || [[ "$(type -p apt-get)" == *apt-get* ]];then
   echo "-------------------------------------------------"
   echo -e "${YELLOW}SYSTEM${NC}  : Unknown"
   echo "-------------------------------------------------"