Atoms panel title is not instrumented

[arouinfar]

Noticed during review for #296 and https://github.com/phetsims/phet-io-client-guides/issues/5

The Atoms & Molecules panel title is editable on the first two screens.

• statesOfMatter.statesScreen.view.moleculesControlPanel.title.textProperty
• statesOfMatter.phaseChangesScreen.view.moleculesControlPanel.title.textProperty

The equivalent Atoms panel on the Interaction screen does not have its title instrumented.

@jbphet this seems like an oversight to me. Can you instrument the panel title? The client does not plan to use the Interaction screen, so I'll leave it up to you to decide whether or not to include this change in the upcoming dev release.

[jbphet]

'Twas indeed an oversight. I instrumented it and added dynamic layout. @arouinfar - please check on master and close if it looks good.

[arouinfar]

Thanks @jbphet! Looks good in master.