Fixed Compilation error due to changes in Kernels clearConstruction Method

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@23151 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Please add a comment to the changed clearConstruction method.

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@23152 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Javadoc

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@23153 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e