Sort package types in documentation

[mfelsche]

Previously they have been unordered, which makes finding them hard, especially for packages with many types (like builtin). This change explicitly does not sort the fields, constructors, methods and behaviours inside a types documentation. Although I would argue that this would also help finding those elements inside a type (e.g. the documentation for chop in Array).

[ponylang-main]

Hi @mfelsche,

The changelog - changed label was added to this pull request; all PRs with a changelog label need to have release notes included as part of the PR. If you haven't added release notes already, please do.

Release notes are added by creating a uniquely named file in the .release-notes directory. We suggest you call the file 4228.md to match the number of this pull request.

The basic format of the release notes (using markdown) should be:

## Title

End user description of changes, why it's important,
problems it solves etc.

If a breaking change, make sure to include 1 or more
examples what code would look like prior to this change
and how to update it to work after this change.

Thanks.

[chalcolith]

I am very much in favour of this, as scanning for things in the pony documentation is a constant source of frustration for me.

[SeanTAllen]

Ah so this is sorting for things that are collected across several files in a package, yes?

[mfelsche]

Ah so this is sorting for things that are collected across several files in a package, yes?

Correct.

[SeanTAllen]

@mfelsche one small change. Please make each paragraph in the release notes a not have newlines. This helps with display in various mediums so that we don't have weird "early" cut offs or "cut-offs that are too late".

Once that is done, I think this is fine to merge.