Updated comments to specify the position of points on the face for 68 points generated by the face landmark detector.

is to clean up the code since it was getting somewhat complex and this is the
last opportunity to do this kind of cleanup prior to the release of dlib v19.0.

If you have saved network objects and want to convert them to the current
format, then make sure you checkout the previous commit (labeled with tag
before_dnn_serialization_cleanup) and then deserialize and serialize your
network back to disk.

* Add cmake option to use external libjpeg on Mac OS

* Add adjust_threshold to python object detector

* Add cmake option to use external libjpeg on Mac OS

* Add adjust_threshold to python object detector

* Revert "Add cmake option to use external libjpeg on Mac OS"

This reverts commit 01f7fd13ea3f2b519312900333f9b68847fd1633.

* Update detector example to set adjust_threshold

DNN Visual Studio 2015 Update3 support

box.

cout.  Also just made it a little nicer with regard to error handling.

written to an output stream.