Create a new RC for RIAW

[zepumph]

This issue is to keep track of where we are with all issues needing to be done before the next RIAW. phetsims/qa#137 was closed, but can be used as a base.

• we also want to make sure that Changing clip area does not work with renderer: canvas scenery#830 (comment) gets in here.

[jessegreenberg]

With #165 and #164 I don't think that phetsims/scenery#830 (comment) will be required for this release anymore.

[zepumph]

• already done, cherry picked this commit phetsims/sun@0ccb537 into sun branch for [keyboard navigation] Adjusting in larger steps then smaller steps doesn't work #160
• cherry pick ffcefb6 for Alerts only work 70% of the time on JAWS and FF 60 #165 which also covers Jaws reading pause on resistivity slider #164.

Looks like we are ready for the next rc after that cherry-pick commit. Good luck us that the merge goes well

[zepumph]

qa issue created in phetsims/qa#179