Expose APIs as an installed package

[BenWinchester]

Issue

CLOVER contains a series of functions which may be useful for users who have installed the clover-energy package. Currently, the __all__ lists are not correctly exposing these APIs.

Proposal

Correctly implement the exposing of these functions as APIs for the end users.

The only alternative is not exposing these APIs and leaving the code as is with four installed access points.

[BenWinchester]

General thoughts

@hamishbeath , this is a fairly code-heavy task - as in, all of the activity involved would likely be code to make CLOVER more Pythonic. It falls under a similar category to #72 (update Python to 3.10), but it is likely a win if we want to use some of the data structures from within CLOVER in other pieces of code, such as the spatial GIS software that we've discussed offline.

I.E., this is likely something that we should do, but the impact is minimal when it comes to a wider user base but makes it easier for other applications to interface with CLOVER 😄

[BenWinchester]

Converting to an issue 😃