Upgrade GXP and OL

A client told me a PR of his has recently been merged in GXP.
By the way CGXP's version of GXP is quite outdated now (Jan 15, 2013 - about 50 commits since then).
Tests still pass and I have noticed no side-effect while testing in a project.

OpenLayers submode is even more outdated (115 commits late). I have also tried to update it (b8bbfe57). Tests pass as well and nothing to report when testing the change in a project.