zsync

File Release Notes and Changelog

Release Name: 0.4.1

Notes:
Mainly a security fix release, although the zlib bug patched is unlikely
to be exploited via zsync. The other changes are mostly to improve 
the correctness of the HTTP code.

Changes:
- security fix from zlib-1.2.2
- generate RFC 1123 date strings in HTTP requests
- include port numbers in Host headers
- be slightly more accepting in proxy URL syntax
- don't generate Accept-Ranges headers