E57

- Breaking: Renamed some image structs and enums
- Breaking: Renamed point cloud iterator interface
- Breaking: Simplified Point struct and removed options
- Breaking: Removed Point constructor from raw values
- Added missing feature to add/write images in E57 files
- Added new simple point cloud iterator with some useful options
to apply pose, skip invalid points, convert spherical to Cartesian
coordinates and convert intensity to color.
- E57 to XYZ tool now respects and includes poses
- E57 to XYZ tool now reads all point clouds of the input file

- Fix: Allow empty translation and rotation for poses

- Breaking: Refactored some Record related prototype types
- Breaking: Removed simple XYZ RGB writing interface
- Added generic E57 point cloud writing for arbitrary point attributes
- Set optional XML root element metadata when writing
- Set optional point cloud metadata when writing

- Breaking: Renamed E57 struct to E57Reader
- Added basic E57 writing support for XYZ RGB point clouds

- Added extract images example tool
- Minor documentation improvements

- Breaking: Fixed some typos in coordinate struct names
- Breaking: Changed CRC validation interface
- Breaking: Changed XML extraction interface
- Added functionality to read images from E57 files
- Use buffered reader for faster E57 file reading
- Added XML-extractor as example code
- Added E57-to-XYZ converter as example code
- Added CRC-validator as example code