Tracklib

- change function names that compute AF
- fix bug in raster
- add last point in spatial linear interpolation
- fix and test operator
- fix CENTERED_FINITE_DIFF, FORWARD_FINITE_DIFF, BACKWARD_FINITE_DIFF operators + unit tests
- fix segmentation+split in TrackCollection
- fix bug read GPX files directory
- rename module with all characters in lowercase

- import manager with __init__ files
- fix bugs

Fixed the logging bug

First release