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>

Signed-off-by: Gergely Kiss <mail.gery@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>

Update several dependencies, as well:

* django-compressor -> 2.1.1
* django-constance -> 1.3.4
* django-restframework -> 3.5.4
* django-statici18n -> 1.3.0
* django -> 1.8.17
* openpyxl -> 2.4.2
* python-dateutil -> 2.6.0
* python-urllib3 -> 1.20

Signed-off-by: Gergely Kiss <mail.gery@gmail.com>

Signed-off-by: Gergely Kiss <mail.gery@gmail.com>

Signed-off-by: Gergely Kiss <mail.gery@gmail.com>

Signed-off-by: Gergely Kiss <mail.gery@gmail.com>

Signed-off-by: Gergely Kiss <mail.gery@gmail.com>

Signed-off-by: Gergely Kiss <mail.gery@gmail.com>

Avoids source filename conflicts and the need to delete source packages
at the end of the prepare stage. This has forced the buildenv to rebuild
the packages even if they were built already.

Signed-off-by: Gergely Kiss <mail.gery@gmail.com>

Signed-off-by: Gergely Kiss <mail.gery@gmail.com>
Tested-by: Gergely Kiss <mail.gery@gmail.com>