PGPT with some symbols draws extra lines between points

[xspector]

Using PGPT with symbols 4, 8, 10, 20-27 causes extra lines to be drawn between the points. The reason is that cairo_arc starts by drawing a line from the current position to the start of the arc requested. The solution is to call cairo_new_sub_path before the call to cairo_arc.

To fix this change in giza-points.c the routines _giza_point, _giza_rect_concave, and giza_circle_size. Note that in _giza_circle you could also replace the call to cairo_move_to by cairo_new_sub_path for simplicity and code parellelism.

The diff between fixed and original versions of giza-points.c is
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< cairo_new_sub_path (Dev[id].context);
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< cairo_new_sub_path(Dev[id].context);
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< cairo_new_sub_path (Dev[id].context);