Verbatim copy of ParseAMSurfToContourList/plot3dsurface

* AnalysisSuite c08f374192bfba0046d4ca43a2a12c072afaade6
remove use of <<-

* probably for debugging long ago
make sure that hxsurf is first listed object type

* dispatch happens from left to right so more specific class must come first
General cleanup of ParseAMSurfToContourList -> read.hxsurf
Add test for read.hxsurf
Clean implementation of plot3d.hxsurf
fixes and tests for colour handling in plot3d.hxsurf