Ready rc.3

[zepumph]

It will be good to keep track of work done in between rc.2 and rc.3. I can do that here

• Over in Need to double check that Size of Arrows and Effort of Robots (cancel out) #182 there were two bug fixes committed to master and the branch. Nothing more should be needed for them.

[jonathanolson]

It looks like the patch for phetsims/phet-core@b9b6761 was not applied in the release branch. It should be included somehow.

[zepumph]

Alright thanks @jonathanolson, I'll publish a new rc hopefully today with that in it.

[zepumph]

So long as we get the all-clear on screen shot over in #24 we will be ready for this final (?) RC.

[zepumph]

phetsims/qa#441