Downgrade Apache httpclient to 4.5.2.v20170210-0925

Downgrade Apache httpclient to 4.5.2.v20170210-0925

Eclipse platform uses this version from the Oxygen Orbit release for
Photon. In order to avoid that we end up with two slightly different
versions in the same p2 repository of the simultaneous release we
downgrade temporarily from the version 4.5.2.v20180410-1551 in the
Photon Orbit release.

See
https://dev.eclipse.org/mhonarc/lists/cross-project-issues-dev/msg15659.html

Change-Id: Id46a840aa4b1010af7fe311498f17f1f2e5b81e0
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>