hiawatha: bump to version 8.3

Bump hiawatha to version 8.3 - adds reverse proxy functionality.
Also define WORK_DIR to /var/lib/hiawatha instead of the uncommon
/usr/var/lib/hiawatha - missed it in the last path fixes.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>