246f9b5285
While the use of relative Urls for referencing included plugin repositories works nicely when cloning directly from gerrit-review, it caused problems when cloning from a mirror that only mirrored the main gerrit repository. There 'git submodule update' did not work unless the referenced plugin repositories were also mirrored in exactly the same relative position as on gerrit-review. Hence, we switch to referencing the included plugin repositories by absolute Urls. Change-Id: I1230f398cc7d2323922aff7f7acf92eac30f3ab5