Try to link tests on Mac.
Fix inaccurate pad brim size
fix build on mac (attempt 2)
Fixes for support tree faults and race conditions in release mode.
Fix crashing test executable on gcc 4.9
fix warning on msvc
All requested config values are written into SL1 ini file inside the zip
* TIme.hpp and Time.cpp is now part of libslic3r instead of libslic3r_gui
* Updated time manipulation function: separate timestamp_local_str and timestamp_utc_str
* timestamp_utc_str is used in header_slic3r_generated(). Gcode now contains UTC timestamps