[FS-1142] Extended numeric literal

[ijklam]

Description

Implement fsharp/fslang-suggestions#445, fsharp/fslang-suggestions#718, fsharp/fslang-suggestions#754

RFC fsharp/fslang-design#770

Fixes # (issue, if applicable)

Checklist

• Test cases added
• Performance benchmarks added in case of performance changes
• Release notes entry updated:

[github-actions]

❗ Release notes required

@Tangent-90,

Caution

No release notes found for the changed paths (see table below).

Please make sure to add an entry with an informative description of the change as well as link to this pull request, issue and language suggestion if applicable. Release notes for this repository are based on Keep A Changelog format.

The following format is recommended for this repository:

* <Informative description>. ([PR #XXXXX](https://github.com/dotnet/fsharp/pull/XXXXX))

See examples in the files, listed in the table below or in th full documentation at https://fsharp.github.io/fsharp-compiler-docs/release-notes/About.html.

If you believe that release notes are not necessary for this PR, please add NO_RELEASE_NOTES label to the pull request.

You can open this PR in browser to add release notes: open in github.dev

Change path	Release notes path	Description
src/Compiler	docs/release-notes/.FSharp.Compiler.Service/8.0.400.md	No release notes found or release notes format is not correct
LanguageFeatures.fsi	docs/release-notes/.Language/preview.md	No release notes found or release notes format is not correct

[abelbraaksma]

Great that you're looking into this, I'd really love this feature! But keep in mind that these proposals do not yet have an RFC (at least not one that I could find).

[ijklam]

Great that you're looking into this, I'd really love this feature! But keep in mind that these proposals do not yet have an RFC (at least not one that I could find).

I will make an RFC later

[ijklam]

Great that you're looking into this, I'd really love this feature! But keep in mind that these proposals do not yet have an RFC (at least not one that I could find).

Added