Protect against path-traversal when downloading.
Protect against path-traversal when downloading.

Due to the way the path is built I don't think any real funny business
is possible on Linux or other systems where the only path separator is a
forward slash like God intended (other than causing the download to fail
with an interesting message by passing something like "." or ".."), but
all bets are off if there is a non-forward-slash path separator.
Arbitrary file writes were probably possible.

BranLwyd/rss-download