Issue #779 Fix - Check Glimpse is enabled in DataBoundControlAdapter

When Glimpse is enabled and then disabled the DataBoundControlAdapter is still registered but GlimpseConfiguration.GetConfiguredTimerStrategy()() returns null. Defensive checks added so event listeners only added when Glimpse enabled.
@CGijbels Couldn't use GlimpseConfiguration.RuntimePolicyStrategy() because couldn't access Glimpse context from the ControlAdapter (it's not like a normal Inspector). Also I tried moving the Adapter registration into Setup but the DataBoundControlAdapter wasn't registered successfully. Try it yourself and you'll see that the DataBound information doesn't appear in the tab.