* ImageReder new option and bug fix in GPS priors
* Add camera_mode option to feature_importer
* Minor feature_importer update
* Update Bitmap and CameraMode documentation
* Fix typo in coment
* Fix another small typo
* Update image_reader.h
* Update bitmap.cc
* Update colmap.cc
* Change camera mode handling in ImageReader
* Update CameraMode documentation
Co-authored-by: Antonios Matakos <anmatako@dss.microsoft.us>
Co-authored-by: Johannes Schönberger <jsch@demuc.de>