Add support for Binding in Components

[TimLariviere]

Components only supports local state through the use of Context.State(defaultValue).
With Context.Binding(stateValue), a component can take a dependency on the local state of another component and be able to listen to changes as well as update the value, triggering a refresh of both components.

Usage:

// Children
let firstNameView (value: StateValue<string>) =
    Component() {
        let! firstName = Context.Binding(value)
        Entry(firstName.Current, firstName.Set)
    }

let lastNameView (value: StateValue<string>) =
    Component() {
        let! lastName = Context.Binding(value)
        Entry(lastName.Current, lastName.Set)
    }

// Parent
let parentView () =
    Component() {
        // Parent is the one owning the data
        let! firstName = Context.State("")
        let! lastName = Context.State("")

        VStack() {
            Label($"Full name is {firstName.Current} {lastName.Current}")
            firstNameView firstName
            lastNameView lastName
    }

[edgarfgp]

Awesome work