Consider changing “when distance < 5” hats to “when distance is close”

[ericrosenbaum]

The WeDo and EV3 extensions both have "when distance" hats. They are slightly different from each other, and both are potentially confusing.

WeDo: when distance [<, >] 50

EV3: when distance < 5

The WeDo hat lets you choose less than or greater than (this is a pre-existing block in scratch 2). The EV3 hat has a smaller default value (because the sensor has a larger physical range).

We have noticed in workshops that kids are sometimes confused by these unit-less sensor values. We have also noticed that the "distance >" option is not often used.

We should consider changing the hat in both extensions to "when distance close", with a threshold set internally (probably 50 for WeDo and 5 for EV3).