Feature Request: option to only refresh the page when the tab is frontmost and visible.

[fiveNinePlusR]

It would be nice to have browser sync have an option to not refresh the page when it is not the frontmost visible tab in a window. Not sure how possible this is with the architecture as it stands.

[shakyShane]

we could check if the tab is active here, https://github.com/BrowserSync/browser-sync/blob/master/packages/browser-sync-client/lib/effects/browser-reload.effect.ts#L18