WPILib Spark and Encoder classes not working?

[RaskorTheWise]

Hello all,

I'm the lead programmer on my team and have been programming for the team for three years. Today, while trying to deploy code to the robot, I encountered something I have never seen before. Cleaning the project works, but building the project produces an error claiming that IterativeRobot is not an accessible base of Robot (our robot class). Additionally, when trying to deploy, the 4 errors increase to 43, because the code refuses to recognize the Encoder or Spark classes either. What's going on, and how can I fix it?

You can find the code on our GitHub here: https://www.github.com/PenguinEmpire/FRC2017

Thanks for any help you can provide,
Noah Gersh
Team 2551