fix Makefile chmod (644)
replace MD5SUM with HASH
add PKG_MIRROR_HASH when PKG_SOURCE_PROTO:=git

(PKG_SOURCE_PROTO:=svn tarballs are not reproducible for now)

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

quassel-irssi is an irssi plugin that allows irssi to connect to
Quassel cores. Quassel is a distributed IRC client in which the
core can run independently and be connected to by quassel clients
over the network.

Signed-off-by: Ben Rosser <rosser.bjr@gmail.com>