Clean/Rebuilds often required for changes in modules to be included

[mxcl]

Seems like an Xcode 10.2 bug since I only noticed it then (saw others on Twitter say same).

• Changes to model and deps only get put in final binary if clean build occurs
• Pretty sure this wasn't always case so either Xcode 10.2 bug or our dependency logic is bust somehow.
• Maybe worth trying making recursive deps explicitly specified.