Support for Files and Images, rewritten summarization functions
- Renamed ExistingPath to File
- Renamed ImagePath to Image
- Version bump to 0.4.2
- Summaries: return series instead of dict
- Categorical: unicode counts now based on original character distribution instead of unique characters which are used as intermediate step for increased performance.
- Categorical: aggregate functions are included for string length (min, max, mean, median).
- Path: number of unique values for the path parts are returned
- Image: make Exif and Hash calculations optional. Also return width, height and area.
- File: in addition to the file_size, return creation, modification and access time (which were already returned).