[backend] do remote getbinaries and binaryversions requests in chunks

This keeps the URLs small, as we don't know if the remote server
can handle long URLs.

Conflicts:
	src/backend/bs_srcserver
[backend] fix project wide hostlabel constraints type conversation
[backend] fix mergeconstraints for physical memory
[api] support new CVE-YYYY-NNNN* syntax as specified by mitre.org

http://cve.mitre.org/cve/identifiers/syntaxchange.html

Conflicts:
	src/api/db/structure.sql
[dist] Start-Before is not official and must be X-Start-Before.

This fixes hopefully the systemd init support
[dist] ensure not to remove the server partition
[backend] further tweak parsing of the project config

Fixes bug that caused a dangling Macros section not to be closed.
[backend] link_or_copy: unlink the target before linking

Otherwise the code will truncate the file in the cache
if the link already exists for whatever reason.
[backend] fix dclone call, it cannot clone non-refs
[backend] fix hostlabel constraints merging
- 2.4.5 release notes
[backend] ensure that new and legacy rpm-md repos get produced
[backend] enforce sha256 for newer rpm-md repositories
[backend] validate suse and rpm-md format with product informations
[api] adapt new test cases for 2.4 branch
[api] ensure existins of "deleted" project and repository on update
[dist] update spec file of 2.4.5 release
Merge remote-tracking branch 'upstream/2.4' into fedora-2.4

Conflicts:
	dist/obsapisetup
	dist/obsstoragesetup