Add requirements param to more Command APIs (#2059)

Assorted improvements to the ergonomics of declaring requirements in the new
command framework. C++ requirements list parameters have been defaulted
to an empty list, some missing C++ requirements list parameters have been
added, and both C++ and Java have been given requirements list params in
various InstantCommand wrapper methods (#2049), whose value is
forwarded to the command.

wpilibNewCommands/src/main/native/include/frc2/command/RamseteCommand.h

@@ -91,7 +91,7 @@ class RamseteCommand : public CommandHelper<CommandBase, RamseteCommand> {
                  frc2::PIDController leftController,
                  frc2::PIDController rightController,
                  std::function<void(units::volt_t, units::volt_t)> output,
-                 std::initializer_list<Subsystem*> requirements);
+                 std::initializer_list<Subsystem*> requirements = {});
 
   /**
    * Constructs a new RamseteCommand that, when executed, will follow the