pcb-rnd 3.1.6
~~~~~~~~~~~~~

This release features a lot of bugfixes and new features; highlights:

1. librnd's polybool2 is testable (need to enable it:
   ./configure --enable-polybool2

2. new alien file format: io_easyeda, for loading easyeda std and pro
   boards and footprints; please ./configure with --buildin-io_easyeda

3. non-modal viewport dialog that gives an exrta view in a separate window
   (zoomable/scrollable)

4. cam job for jlcpcb assembly service (pick and place files)

5. mincut critical bugfix; the bug rendered mincut not delivering the result
   it conputed on shorts

6. svg export: selectable colorspace

7. toolpath based HP-GL export - usable for paint removal with pen plotter
   (home board etching)

8. relaxed rules in object id verification: accept hier-sep (normally '/')
   in refdes but not in terminal name; this makes the syntax a/b/c-4 with
   no / or - after the first and only -

9. bugfixes: proper support for crescent padstacks (hole/slot cutting
   the "ring")

10. bugfixes on gfx object (pixmap): buffer transformations affect the object

11. padstack clearance in polygon recomputed after padstack prototype modified
    (padstack shape changed)

12. floating fhs support for Ringdove binpack

13. bom export format for part-rnd

14. alien format: io_pcb upgrade for reading file format 20180318
