title: Use of undeclared type "Firebase"
body: <p>I installed cocoapods using "sudo gem install cocoapods" and followed the very basic instructions from Firebase along with many tutorials to install the frameworks, yet I keep getting this error when I try to create my first reference. The file lets me import Firebase without error, it lets me use FIRApp.configure() without error, but when I want to make a Firebase reference I can't do it. Any help would be much appreciated, thank you. </p>
  
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