title: Implicitly import specific Swift module
body: <p>I use a third party Swift framework in my Swift app very often and would like to use it without having to write <code>import ModuleName</code> in every single Swift file over and over again.</p>
  
  <p>Is there a way to specify default imports like it was possible in Objective-C using a <code>.pch</code> file?</p>
  
  <p>I already checked Xcode build settings and <code>swiftc</code> flags but none of them offers this functionality.</p>