[test][buffer] enhance svg display for test results and deflated polygons.
By default pieces/turns are non visible now
[test][buffer] uncommented deflated indentation tests, which pass now
[test][buffer] more deflation tests and move order
[test][buffer] test ccw by default
[test][buffer] add deflate test for multi, including failing for distance=half of square
[test][buffer] add simplex square for failing deflate case
[test][buffer] remove _neg suffix from test-case-name, it is done automatically