Adaptions to test with respect to new namespace model
Removed GMP/CLN and, where it was present, replaced by TTMATH
Small fix in comparable_distance test
All testfiles use bg as alias now
[SVN r66811]
-> added many testcases
Various updates in testcases for support of open polygons
recursive_boxes.cpp, added triangles as well (dropped corner)
[SVN r66450]
Added test for remove_spikes
Small changes in tests for differences, sectionalize
Enhanced write_svg in the sense that .x()/.y() are removed, plus using max to avoid empty nonvisible boxes
[SVN r61020]
