Rename "Interactive Descriptions" to "Interactive Description" across the project

[zepumph]

I hear @terracoda over in #145 (comment). We should make sure to fix this across the project

Currently there are 23 usages of interactiveDescriptions, and 19 usages of "interactive descriptions" (case insensitive).

@jessegreenberg whoever get's this this first.

[jessegreenberg]

Dependencies have been updated for release branches in phetsims/phetmarks#48. The only exception a phet-io specific release branch of molarity which will be taken care of separately in that issue.

I verified that phetmarks is launchable from atomic-interactions 1.2 SHAs again. @jbphet reassigning to you to verify if you wish, otherwise I think this can be closed.

[jbphet]

I tested this by checkout out the 1.2 branch of atomic-interactions and testing phetmarks, and it worked fine. Thanks for the fix @jessegreenberg and @zepumph. Closing.