Make 'help' feature sections collapsible

[Pactionly]

Currently the help feature provides details about all of Gratibot's functionality in a single block of help text. This can be overwhelming when looking for a basic overview of functionality, or when looking for details about a single feature.

Redesign the help function to better break text into general and specific details, and allow some way for users to select a level of details for different functionality.
Some possible ways of accomplishing this would be implementing collapsible help sections, which users could expand as needed, or using extra parameters to provide specific help details, such as @gratibot help leaderboard