Integration of PRESELECTION_AFFINE_TRANSFORM and h5_to_bundler.py

[fdahle]

Support for tiling with affine transform:

• similar to PRESELECTION, tie-points are matched with with a downsampled version
• an affine transformation is fit with the points (if >3; otherwise the default preselection is used)
• transformation is used to calculate the extent of the tiles for matching

Furthermore inclusion of h5_to_bundler.py:

• Allows exporting to a bundler file, which can be used e.g to import tie-point matches into Agisoft Metashape
• bundler file can be created with descriptors or without (then just based on px_tolerance)