[FS-1142] Extended numeric literal

[Tangent-90]

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).

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

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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).

[Tangent-90]

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

[Tangent-90]

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