Remove "Related" and "Used By" sections.

[StevenDufresne]

While there may be cases where users are interested in discovering related functions, the related list doesn't seem to accomplish that and probably ends up creating a more complicated experience.

When viewing the activate_plugin reference I get:

[tellyworth]

I use both at various times, usually when I'm trying to make sense of execution flow. We could consider using Expand buttons, or moving them to a separate page/section.

[iandunn]

Would it be helpful to display call stacks? eg.,

plugins.php -> activate_plugins() -> activate_plugin() -> validate_plugin() -> validate_file() ...

Many functions would have multiple callers and callers though, so some kind of flow chart or network graph might be needed. There may already be code out there that does something like this.

When there are more than a handful of paths, though, it may become too unwieldy to be useful; at least without some interactive tools to filter down to which paths you want, etc.