Added an "overlap" member variable to fill classes in the preparation
for futher move of the "infill / perimeter" overlap to the Fill class.
Moved the orientation predicates from Fill to Geometry.
Removed GCode.pm
Removed the Perl bindigns for AvoidCrossingPerimeters, OozePrevention, SpiralVase, Wipe
Changed the std::set of extruder IDs to vector of IDs.
Removed some MSVC compiler warnings, removed obnoxious compiler warnings when compiling the Perl bindings.
