TAChart: Clear patterns cache in TSVGDrawer.DrawingEnd

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@40139 4005530d-fff6-0310-9dd1-cebe43e6787f
TAChart: Support monochrome mode in AggPas drawing back-end


git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@40140 4005530d-fff6-0310-9dd1-cebe43e6787f