Clarify that ‘App.xcodeproj’ has to be substituted by the user’s application project.
Clarify that ‘App.xcodeproj’ has to be substituted by the user’s application project.

Closes #53.

orta/Core,brianmichel/Core,dnkoutso/Core,Ashton-W/Core,k0nserv/Core,CocoaPods/Core,gabro/Core,dacaiguoguogmail/Core,AdamCampbell/Core