issue598 file open - remember the last directory 'file open' was in and reuse
bug rept per Michael at Oz
add PRINTD to printutils.cc
add PRINTD to printutils.h
add '--debug=' option to openscad cmdline. see printutils.h for usage
add global OpenSCAD::debug string to printutils.cc (see printutils.h for usage)
replace logstream with PRINTD / PRINTDB . add boost include to printutils.cc
fix PRINTD to PRINTDB
Add a testcase for a bug with self-intersecting polygon outline
Merge branch 'unstable' into printd0
Merge branch 'unstable' into issue598fo
Added --debug to usage
Renamed setting to be in sync with other file settings
Started on hacking doc
Merge branch 'unstable' of github.com:openscad/openscad into unstable
Merge branch 'unstable' of github.com:openscad/openscad into unstable
Merge pull request #626 from OskarLinde/ui_find

Editor: Implemented simple Find functionality
toPolygon2D() now use Clipper's cleaning algorithm

The old polygon simplification algorithm in toPolygon2D() was broken.
It could create self-intersecting paths which made CGAL barf and
resulted in non-manifold meshes. It has been replaced with the one
built into Clipper. I am not sure Clipper's is guaranteed to be
correct either, but it at least seems to have fewer fail cases.
Merge branch 'poly2_bug' of git://github.com/OskarLinde/openscad into OskarLinde-poly2_bug
Simplified and renamed test related to #612
Editor: Fix bug where replaceAll could enter an infinite loop