Include type constraints in documentation

The [documentation for `hash`](https://fsharp.github.io/fsharp-core-docs/reference/fsharp-core-operators.html#hash) does not say that it requires the `equality` constraint on its only type parameter. Another example is the [documentation for `compare`](https://fsharp.github.io/fsharp-core-docs/reference/fsharp-core-operators.html#compare). It requires the `comparison` type constraint on its only type parameter. For convenience, here is the [list of all type constraints](https://docs.microsoft.com/en-us/dotnet/fsharp/language-reference/generics/constraints).

Could type constraints be added to the documentation for types that have them?