[DEVOPS] Add README and update cleanup method for certificates

deployment/environments/certs/client-external/ca/README

+Put your external clients certificates' CA here (.crt)
\ No newline at end of file

deployment/environments/certs/client-external/clients/external/README

+Put your external client public certificates here (.crt)
\ No newline at end of file

deployment/environments/certs/client-vitam/ca/README

+Put your Vitam certificates' CA here (.crt)
\ No newline at end of file

deployment/environments/certs/client-vitam/clients/README

+Put your Vitam certificates here (.crt)
\ No newline at end of file

deployment/pki/scripts/generate_certs.sh

@@ -278,7 +278,10 @@ initVault   certs   ${ERASE}
 if [ "${ERASE}" == "true" ]; then
     if [ -d ${REPERTOIRE_CERTIFICAT} ]; then
         # We remove all generated certs
-        find "${REPERTOIRE_CERTIFICAT}/" -mindepth 1 -maxdepth 1 -type d -exec rm -Rf {} \;
+        find ${REPERTOIRE_CERTIFICAT} -type f -name *.crt -exec rm -f {} \;
+        find ${REPERTOIRE_CERTIFICAT} -type f -name *.key -exec rm -f {} \;
+        find ${REPERTOIRE_CERTIFICAT} -type f -name *.pem -exec rm -f {} \;
+        find ${REPERTOIRE_CERTIFICAT} -type d -empty -delete
     fi
 fi
 if [ ! -d ${REPERTOIRE_CERTIFICAT} ]; then