don't override OPENSCADPATH the debian tests scripts already set an adaequate OPENSCADPATH; the overrides in the test scripts would set that wrongly again (because openscad and mcad are not built in the same tree in debian)
for a cleaner solution, the library path should be respected unconditionally, removing the necessity for debian to specify a path at all.
Report Debian versions in test_pretty_print The git repository the test_pretty_print.py script tries to read is available neither at build time nor when run as openscad-testrun; this provides the relevant information for the latter case.
test_pretty_print: remove a pathname normalization step with absolute paths replaced by relative ones in debian (see debian/rules), what's done in test_pretty_print.py by replacing the build dir with nothing causes all '.' characters to be removed again.
for a cleaner solution, absolute path removal should be upstremed.
