* Fixed reference count issue
* Fixed refcount issue in Python dlib.jitter_image and dlib.get_face_chips
* Consolidation of https://github.com/davisking/dlib/pull/1249
* Fixed build issue
* Fixed: Paths in a pytest file should be relative to dlib root
* Skip numpy return tests for Python 2.7 or if Numpy is not installed
* Enabled numpy returns tests on Python 2.7 using cPickle.dumps
* 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 01f7fd13ea.
* Update detector example to set adjust_threshold
