[FAB-5221] generateCerts should delete crypto

It's possible to run byfn -m generate multiple
times depending on how you go through the
tutorials, start/stop the network, etc.
The crypto-config folder is deleted when
running byfn -m down and that will stay,
but now each time generateCerts is run the
cyrpto-config folder will be deleted as well.

Change-Id: Ie3851debd76ff0c50c84e14fbca56de2a28bd825
Signed-off-by: Gari Singh <gari.r.singh@gmail.com>

first-network/byfn.sh

@@ -204,6 +204,9 @@ function generateCerts (){
   echo "##### Generate certificates using cryptogen tool #########"
   echo "##########################################################"
 
+  if [ -d "crypto-config" ]; then
+    rm -Rf crypto-config
+  fi
   cryptogen generate --config=./crypto-config.yaml
   if [ "$?" -ne 0 ]; then
     echo "Failed to generate certificates..."