[contrib] verifybinaries: Keep downloads by default

contrib/verifybinaries/README.md

@@ -12,3 +12,9 @@ Usage:
 ./verify.sh bitcoin-core-0.12.0
 ./verify.sh bitcoin-core-0.13.0-rc3
 ```
+
+If you do not want to keep the downloaded binaries, specify anything as the second parameter.
+
+```sh
+./verify.sh bitcoin-core-0.13.0 delete
+```

contrib/verifybinaries/verify.sh

@@ -111,8 +111,13 @@ elif [ $? -gt 1 ]; then
    exit 2
 fi
 
-#everything matches! clean up the mess
+if [ -n "$2" ]; then
+   echo "Clean up the binaries"
    clean_up $FILES $SIGNATUREFILENAME $TMPFILE
+else
+   echo "Keep the binaries in $WORKINGDIR"
+   clean_up $TMPFILE
+fi
 
 echo -e "Verified hashes of \n$FILES"