Add Option#mapTry()

[bvkatwijk]

Add mapTry method to Option, which is a shortcut for .toTry().mapTry:

• when mapping an optional using a checked method, I find it intuitive that the type changes to a Try, and mapTry methods exist on other types already
• I initially added it onto Value but this ran into an issue where a method with same name but return value already exists on subtypeFuture

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Rebase of #2950

[pivovarit]

Looking good, thanks!