Adapt move_x_axis when xzero is outside the screen (on left)
Adapt move_y_axis when yzero is outside the screen (below)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@36437 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
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git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@36438 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e