Swipe to pick up wire

[KatieWoe]

For phetsims/qa#306. I noted that the bit of wire you move to connect/disconnect different parts of the circuit doesn't have swipe to pick up. But the touch areas are pretty good sized. Since we are looking at phetsims/qa#295, I thought it might be useful to look at.

[phet-steele]

@KatieWoe this feature (swipe to pick up) is called touchSnag. Please see #130 for why touchSnag was disabled, mostly starting at #130 (comment). @arouinfar be aware what you would be reintroducing if you are looking at this for phetsims/qa#295. I don't think it's a worthwhile trade-off to revert all the time spent in #130.

[KatieWoe]

Thanks @phet-steele sorry for missing that.

[arouinfar]

Thanks for the reminder @phet-steele! Since there isn't any real usability issue on touch, I think we can continue leaving touchSnag disabled.