Measurement Widget should Suppress Feature Popup / Selection on Click

[jcarlson]

When I am using the measure tool, clicking to add a vertex to the measurement line/area will also select any underlying feature. At best, it's a minor annoyance, and the repeated popup calls make the whole measuring process take longer than necessary.

At worst, it's an actual impedance to some of our users who are trying to measure along one or more selected features. When they click slightly over the boundary onto the next feature, their selection changes. They cannot then re-select the original features without altering their measurement sketch or starting over.

There should be some way for the measurement widget to suppress click selection / popups in the map while active.