[WIP] Add option to do sparse distance matrix calculation

[cchwala]

This PR add the option to do sparse distance matrix calculations to the existing function calc_point_to_point_distances.

• related to Fast nearest neigbor lookup with KDTree #37 (but only partial implementation and does not close it)
• Tests added and passed if fixing a bug or adding a new feature
• All code checks from pre-commit passed
• Added an entry in the CHANGELOG.md file

[cchwala]

Note to myself: See the updated info in #37 (comment) with the idea to set custom fill_value in COO sparse matrix.