[wpilibc] Transition C++ classes to units::second_t (#3396)

A lot of these are breaking changes. frc::Timer was replaced with the
contents of frc2::Timer. The others were in-place argument changes or
removing deprecated non-unit overloads.

wpilibcIntegrationTests/src/main/native/cpp/TestEnvironment.cpp

@@ -53,7 +53,7 @@ class TestEnvironment : public testing::Environment {
         std::terminate();
       }
 
-      Wait(0.1);
+      Wait(0.1_s);
 
       wpi::outs() << "Waiting for enable: " << enableCounter++ << "\n";
     }