genswap.sh: check for gawk before main

Former-commit-id: dfc001cb8a93ef514d938785f6216ead503833bd

genswap.sh

@@ -6,7 +6,10 @@ TOTALRAM=$(free -m | gawk  '/Mem:/{print $2}')
 VERSION="0.1.0"
 BUILDDATE="2018-06-05"
 
-
+if [ ! -f /usr/bin/gawk ];then
+    echo -e "\nPlease install 'gawk' with your package manager\n"
+    exit 0
+fi
 function autoSwap(){
         echo -e "\nTotal Physical RAM is: ${TOTALRAM} MB\n"
         echo -e "\nCreating a ${TOTALRAM} MB file in:${SWAPPATH}..\n"