827e39354a
1) Implement redirects (or try to, at least). 2) Implement automatic retry after 503 errors when Retry-After is given. 3) Implement a -a flag to enable both of these behaviors. 4) Recognize Transfer-Encoding headers and emit a warning that the file is likely to be damaged. 5) Bug fix: only write the amount of data we read. 6) Actually document some of these. 7) Fix the usage message to display flags in semi-alphabetical order.