Navigation path incorrect for exercises.

[rookiehpc]

When accessing an exercise, such as the MPI hello world, the navigation path shows ... > Exercises > undefined.

The reason is the rk.js script loads the property RK.NamePN, which, for exercises, does not exist as they have a RK.TitlePN property instead.

A solution would be to either:

• Try RK.NamePN and revert to RK.TitlePN if it failed.
• Change the exercise JSON record structure to use a RK.NamePN property instead of RK.TitlePN one.

In addition, this check could be added to the rk.js script to prevent similar mistakes in future.