Switched URL to a sensible one.

Some Makefile rearrangements for consistency.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

This guarantees for the package feeds that
the mk files will always be available for all packages.

Will need to see about external-feed Python packages
a bit later.

Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>

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>

Signed-off-by: Daniel Golle <daniel@makrotopia.org>