Enhancement on Statusbar

[ichan-mb]

Android.StatusBarConfig added Style property to change status bar text color to Dark or Light. Introduce SetStatusBarUI trigger action to set the look and feel of the status bar

Example:

    <App>
        <Android.StatusBarConfig Style="Dark" Color="#FFF" />
        <Page Color="#EE430A">
            <Activated>
                <SetStatusBarUI Style="Light" Color="#EE430A" />
            </Activated>
        </Page>
    </App>

This PR contains:

• [x] Changelog
• [x] Documentation
• [ ] Tests