Re-add search mag feature

# Update Magnifying glass

The last update to the view tree took that :mag_right: out of action for a hot minute. This brings it back with a vengance.

New features include:
+ a new highlight mask that is always on top
+ "scrolling" clicking on the page element scrolls the view into focus in the inspector

watch the mind numbing gif for more info :)

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![](http://f.cl.ly/items/1s1Q282K0t1m0K3G2M0T/mag-awesome.gif)


#### Task breakdown
+ add mag to the nav
+ add efficient row unhlighlting
+ turn the search button on and off
+ log the view from the treeView code
+ fix UI event binding bug where the UI was receiving client events twice
+ update highlighting to use a mask that's above the page
+ scroll the inspector view into view on mag click
+ add sendMessage immediate for when you want to immediately send a
message
+ when there's a url refresh event we should check in a bit to see if
the agent is still there... sometimes it's not really a refresh...
This is probably exactly why we were seeing the little blue highlight pixel last night :D. I think setting `visibility:hidden` or `display:none` might be a better solution.