File/folder (and some function) structure needs slight redesigning

[tdmalone]

Slackémon was originally part of another framework but since moving out has both retained the original structure of that framework and added additional integrations such as CI. Configuration for additional integrations pollutes the root folder, especially when there's some source code mixed in there too. In addition, from the original framework, some of these files do not much else but call counterparts in the slackemon/ folder... which in turn end up calling functions in _functions/pokemon, some of which use functions directly in the _functions folder.

Some of the functions are also prefixed pokedex_ rather than slackemon_, which reflect that that they were originally written for a Pokédex feature part of the same framework Slackémon came from.

Whew! So basically, the structure needs rethinking so it's clear and less confusing. At the same time, we should clear the root folder of any source code, and try to put some of the directly run code into functions where they can be properly tested.

[tdmalone]

This restructure is now in progress on https://github.com/tdmalone/slackemon/tree/tim

[tdmalone]

In line with #32 this restructure has now moved to https://github.com/tdmalone/slackemon/tree/file-restructure-%2326

[tdmalone]

• [x] Re-organise folder structure so it makes more sense (now in develop)
• [x] Move most source code out of root folder (now in develop)
• [x] Re-prefix the pokedex_ functions as slackemon_ (now in develop)
• [x] Move most directly run code into functions (in progress on file-restructure-#26)
• [x] Prefix most other non-prefixed functions as slackemon_