Support for SALR Redux

Uses chrome.management to see if Redux is installed/enabled and if it
fails (either .enabled will be false or undefined will trip), falls back
on trying to use SALR (original).

Seems to work when:
both installed and enabled (uses Redux)
both installed and one enabled (uses enabled one)
one is not installed (uses installed one)
both not installed (doesn't work obviously)
neither enabled (doesn't work obviously)