utils

Provide various helper functions for use across the package.

Data directories

`cdd_geofabrik`(*sub_dir[, mkdir, default_dir])	Change directory to `osm_geofabrik\` and its subdirectories within a package.
`cdd_bbbike`(*sub_dir[, mkdir, default_dir])	Change directory to `osm_bbbike\` and its subdirectories.

`first_unique`(iterable)	Return unique items in an input iterable variable given the same order of presence.
`check_json_engine`([engine])	Check an available module used for loading JSON data.
`remove_osm_file`(path_to_file[, verbose])	Remove a downloaded OSM data file.