More test fiddlyness that needs amending
Add some tests. Moreover, port tests to checker[1]

clink should have many tests to ensure things don't break going forward
as maintenance takes place.

[1] https://github.com/pnathan/checker
Added more tests. Defined the API for casting to a data-frame.

Unit testing demonstrated the lack of being able to send a vector
into the data frame.

Time away from the code revealed that the data frame should have some
form of extensible loading API.
Commenting and adding docstrings
Cleaning up the code
Overhauling the range tree for clarity of code.