cody: lvlgraph: combined properties in NodeStyle

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@40314 4005530d-fff6-0310-9dd1-cebe43e6787f
cody: lvlgraph: published NodeStyle

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@40315 4005530d-fff6-0310-9dd1-cebe43e6787f