* OptmizerG2O: add prior edge export
* add required conditions and structure to export prior edges
* for now, make the graph exportation of priors not dependent of parameters
* include <locale.h> so to use setlocale() in a windows build
* Camera Refactoring part 1 (Mac OS X)
* fixed camera*** -> Camera***
* Fixed build for cameras Zed/RealSense/RealSense2
* increased version to 0.17.7
* fixed build for cameras K4W2 and FlyCapture2